IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Flow And Heat Transfer Characteristics On A Confined Slot Jet Impinging On A ...Dahiru Lawal
This document describes a study on the flow and heat transfer characteristics of a confined slot jet impinging on a constant heat flux surface. The study examines the effects of varying the jet width-to-height ratio (H/W) and Reynolds number (Re) on heat transfer properties. Numerical simulations are conducted to analyze the velocity contours, temperature distributions, Nusselt numbers, and pressure coefficients. Results show that heat transfer rate increases with higher H/W ratios and Re numbers. Flow and thermal fields also become time-dependent and asymmetric if Re exceeds a critical value. Validation of the numerical model is also performed.
New Microsoft Office PowerPoint PresentationSudhir Shinde
This document summarizes a seminar presentation on heat transfer via jet impingement. The presentation discusses how jet impingement is used to effectively remove large amounts of heat from surfaces, such as in cooling turbine blades and electronics. It reviews factors that influence heat transfer, including nozzle diameter, jet-to-surface spacing, and Reynolds number. The experimental setup examines heat transfer characteristics of air and water jets impinging on a heated surface. Results show that lower jet diameters and spacings and higher Reynolds numbers increase heat transfer. The conclusion is that jet impingement is effective for cooling applications due to the high heat transfer coefficients that can be achieved.
Numerical Predictions of Enhanced Impingement Jet Cooling with Ribs and Pins ...AZOJETE UNIMAID
This document presents a numerical study of enhanced impingement jet cooling with ribs and pins on target surfaces. Computational fluid dynamics (CFD) simulations were conducted using commercial codes to predict heat transfer with different obstacle wall configurations. The obstacles investigated were ribs and rectangular pin-fins in both co-flow and cross-flow alignments. The CFD predictions showed good agreement with previous experimental results and revealed that obstacles increase turbulence but also reduce the highest thermal gradients and downstream cross-flow.
IRJET- Study of Jet Impingement Heat TransferIRJET Journal
This document reviews research on jet impingement heat transfer. It discusses the flow and heat transfer characteristics of single and multiple impinging jets. Key factors that influence heat transfer are jet Reynolds number, nozzle-to-plate spacing, jet pattern, and crossflow. The document summarizes various empirical correlations that have been developed to predict average heat transfer coefficients. It also reviews numerical studies on modeling heat transfer for multi-jet systems and discusses the effects of parameters like Reynolds number, nozzle spacing, crossflow, and jet interference.
Heat Transfer Enhancement through Liquid Jet ImpingementIRJET Journal
This document provides a literature review on experimental and computational studies of liquid jet impingement heat transfer. It summarizes various parameters that influence jet impingement heat transfer such as flow rate, nozzle size, inlet pressure, and working medium properties. It then reviews over 30 experimental and computational studies on topics like the effects of nozzle geometry, surface roughness, nanofluids, vortex generators, swirling jets, and more. The overall goal is to provide an overview of recent approaches to studying jet impingement heat transfer processes.
Numerical Simulations on Jet Impingement Cooling of Cylindrical SurfacesIRJET Journal
This document summarizes a numerical study on jet impingement cooling of cylindrical surfaces. Jet impingement exhibits non-uniform heat transfer on cylinders, with maximum heat transfer at the jet stagnation zone and local maxima/minima occurring along the circumference due to transition between laminar and turbulent flow. Parameters studied include jet Reynolds number and cylinder to jet diameter ratio. Results for smooth cylinders matched literature. Heat transfer decreases with Reynolds number from 100 to 1000 but increases beyond 1000. The study aims to address gaps in understanding jet impingement cooling effects on cylinders.
Computational Analysis of Turbulent flow heat transfer and pressure loss in D...IRJET Journal
This document discusses computational analysis of turbulent flow, heat transfer, and pressure loss in ducts or pipes with segmental baffles. Segmental baffles are implemented to enhance flow characteristics and thermal performance. Due to the baffles, significant turbulence is generated, increasing friction with the pipe and improving heat transfer but also leading to greater pressure drop. Finite element analysis is conducted using ANSYS Fluent to simulate turbulent flow over a range of Reynolds numbers in smooth and baffled pipes. Results are validated against published experimental and numerical data and show good agreement. Contour plots illustrate increased turbulence and velocity magnitude in baffled pipes compared to smooth pipes.
Diffusers are extensively used in centrifugal
compressors, axial flow compressors, ram jets, combustion
chambers, inlet portions of jet engines and etc. A small change in
pressure recovery can increases the efficiency significantly.
Therefore diffusers are absolutely essential for good turbo
machinery performance. The geometric limitations in aircraft
applications where the diffusers need to be specially designed so
as to achieve maximum pressure recovery and avoiding flow
separation.
The study behind the investigation of flow separation in a planar
diffuser by varying the diffuser taper angle for axisymmetric
expansion. Numerical solution of 2D axisymmetric diffuser model
is validated for skin friction coefficient and pressure coefficient
along upper and bottom wall surfaces with the experimental
results of planar diffuser predicted by Vance Dippold and
Nicholas J. Georgiadis in NASA research center [2]
.
Further the diffuser taper angle is varied for other different
angles and results shows the effect of flow separation were it is
reduces i.e., for what angle and at which angle it is just avoided.
Flow And Heat Transfer Characteristics On A Confined Slot Jet Impinging On A ...Dahiru Lawal
This document describes a study on the flow and heat transfer characteristics of a confined slot jet impinging on a constant heat flux surface. The study examines the effects of varying the jet width-to-height ratio (H/W) and Reynolds number (Re) on heat transfer properties. Numerical simulations are conducted to analyze the velocity contours, temperature distributions, Nusselt numbers, and pressure coefficients. Results show that heat transfer rate increases with higher H/W ratios and Re numbers. Flow and thermal fields also become time-dependent and asymmetric if Re exceeds a critical value. Validation of the numerical model is also performed.
New Microsoft Office PowerPoint PresentationSudhir Shinde
This document summarizes a seminar presentation on heat transfer via jet impingement. The presentation discusses how jet impingement is used to effectively remove large amounts of heat from surfaces, such as in cooling turbine blades and electronics. It reviews factors that influence heat transfer, including nozzle diameter, jet-to-surface spacing, and Reynolds number. The experimental setup examines heat transfer characteristics of air and water jets impinging on a heated surface. Results show that lower jet diameters and spacings and higher Reynolds numbers increase heat transfer. The conclusion is that jet impingement is effective for cooling applications due to the high heat transfer coefficients that can be achieved.
Numerical Predictions of Enhanced Impingement Jet Cooling with Ribs and Pins ...AZOJETE UNIMAID
This document presents a numerical study of enhanced impingement jet cooling with ribs and pins on target surfaces. Computational fluid dynamics (CFD) simulations were conducted using commercial codes to predict heat transfer with different obstacle wall configurations. The obstacles investigated were ribs and rectangular pin-fins in both co-flow and cross-flow alignments. The CFD predictions showed good agreement with previous experimental results and revealed that obstacles increase turbulence but also reduce the highest thermal gradients and downstream cross-flow.
IRJET- Study of Jet Impingement Heat TransferIRJET Journal
This document reviews research on jet impingement heat transfer. It discusses the flow and heat transfer characteristics of single and multiple impinging jets. Key factors that influence heat transfer are jet Reynolds number, nozzle-to-plate spacing, jet pattern, and crossflow. The document summarizes various empirical correlations that have been developed to predict average heat transfer coefficients. It also reviews numerical studies on modeling heat transfer for multi-jet systems and discusses the effects of parameters like Reynolds number, nozzle spacing, crossflow, and jet interference.
Heat Transfer Enhancement through Liquid Jet ImpingementIRJET Journal
This document provides a literature review on experimental and computational studies of liquid jet impingement heat transfer. It summarizes various parameters that influence jet impingement heat transfer such as flow rate, nozzle size, inlet pressure, and working medium properties. It then reviews over 30 experimental and computational studies on topics like the effects of nozzle geometry, surface roughness, nanofluids, vortex generators, swirling jets, and more. The overall goal is to provide an overview of recent approaches to studying jet impingement heat transfer processes.
Numerical Simulations on Jet Impingement Cooling of Cylindrical SurfacesIRJET Journal
This document summarizes a numerical study on jet impingement cooling of cylindrical surfaces. Jet impingement exhibits non-uniform heat transfer on cylinders, with maximum heat transfer at the jet stagnation zone and local maxima/minima occurring along the circumference due to transition between laminar and turbulent flow. Parameters studied include jet Reynolds number and cylinder to jet diameter ratio. Results for smooth cylinders matched literature. Heat transfer decreases with Reynolds number from 100 to 1000 but increases beyond 1000. The study aims to address gaps in understanding jet impingement cooling effects on cylinders.
Computational Analysis of Turbulent flow heat transfer and pressure loss in D...IRJET Journal
This document discusses computational analysis of turbulent flow, heat transfer, and pressure loss in ducts or pipes with segmental baffles. Segmental baffles are implemented to enhance flow characteristics and thermal performance. Due to the baffles, significant turbulence is generated, increasing friction with the pipe and improving heat transfer but also leading to greater pressure drop. Finite element analysis is conducted using ANSYS Fluent to simulate turbulent flow over a range of Reynolds numbers in smooth and baffled pipes. Results are validated against published experimental and numerical data and show good agreement. Contour plots illustrate increased turbulence and velocity magnitude in baffled pipes compared to smooth pipes.
Diffusers are extensively used in centrifugal
compressors, axial flow compressors, ram jets, combustion
chambers, inlet portions of jet engines and etc. A small change in
pressure recovery can increases the efficiency significantly.
Therefore diffusers are absolutely essential for good turbo
machinery performance. The geometric limitations in aircraft
applications where the diffusers need to be specially designed so
as to achieve maximum pressure recovery and avoiding flow
separation.
The study behind the investigation of flow separation in a planar
diffuser by varying the diffuser taper angle for axisymmetric
expansion. Numerical solution of 2D axisymmetric diffuser model
is validated for skin friction coefficient and pressure coefficient
along upper and bottom wall surfaces with the experimental
results of planar diffuser predicted by Vance Dippold and
Nicholas J. Georgiadis in NASA research center [2]
.
Further the diffuser taper angle is varied for other different
angles and results shows the effect of flow separation were it is
reduces i.e., for what angle and at which angle it is just avoided.
This document summarizes an experimental study on heat transfer enhancement from surface roughness at laminar flow. Specifically, it examines using circular and oval dimples on an aluminum plate to increase heat transfer from the plate to air flowing over it at Reynolds numbers from 600 to 2000. The study finds that both circular and oval dimples enhance heat transfer compared to a flat plate, while maintaining equivalent or lower pressure drops. The experimental results are validated by comparing the measured Nusselt numbers to theoretical values for a plain vertical plate under laminar flow conditions. In general, the dimpled surfaces increase thermal performance without significantly increasing pressure drops compared to a smooth surface.
The document discusses cyclone technology for removing dust particles from air streams. It provides background on cyclone design parameters like pressure drop and collection efficiency. The optimal dimensions of cyclones are discussed, with the 2D2D design being most efficient for particles larger than 20 microns. While models can predict trends, testing is still needed due to complex flow patterns and many influencing factors. The document also reviews classical cyclone design procedures and limitations of models in accurately predicting performance metrics like number of turns and cut-point diameter.
IRJET- Flow and Heat Transfer Charecterstics of Multiple Jet CoolingIRJET Journal
The document summarizes research on heat transfer characteristics of multiple jet cooling for electronic components. Experiments were conducted using an array of 49 water jets impinging on an electrically heated copper plate. The jet diameter was 0.5mm, arranged in a 7x7 square array with 3mm pitch. Tests were run at flow rates of 22-40 ml/min and heat fluxes of 25-200W/cm2. Results showed that heat transfer coefficient, or Nusselt number, increased with increasing heat flux and Reynolds number. Prior studies on jet impingement cooling are also summarized.
IRJET- Study of Fluid Flow Characteristics for the Flow of Air over a Hea...IRJET Journal
This study examines fluid flow characteristics for air flowing over a heated diamond-shaped tube using computational fluid dynamics (CFD) software. The governing equations for steady, incompressible laminar flow are solved. Pressure drop and friction factor are analyzed for both diamond and circular tubes as the Reynolds number is varied from 438 to 1227. Results show that pressure drop increases and friction factor decreases with Reynolds number for both shapes, though the diamond tube exhibits higher values compared to the circular tube due to its larger frontal area. Velocity distributions also indicate a larger wake region behind the diamond tube. The study aims to provide insights into heat transfer for applications involving cross-flow over tubes such as heat exchangers.
IRJET- Investigation of Fluid Flow Characteristics for the Forced Convect...IRJET Journal
This document summarizes a study that used computational fluid dynamics (CFD) to investigate fluid flow characteristics over heated elliptical and circular shaped tubes. The study varied the Reynolds number from 438 to 1227 and found that elliptical tubes had lower pressure drop and friction factor values than circular tubes. Velocity distributions showed smaller wakes behind elliptical tubes. Pressure drop and friction factor both increased with Reynolds number but elliptical tubes performed better in both areas. The study concluded elliptical tubes provided better heat transfer characteristics than circular tubes of the same hydraulic diameter.
3 ijaems jun-2015-17-comparative pressure drop in laminar and turbulent flowsINFOGAIN PUBLICATION
This document summarizes a study that uses computational fluid dynamics (CFD) to analyze laminar and turbulent flows in circular pipes with and without baffles. It presents the following key points:
1) CFD simulations were conducted using ANSYS Fluent to analyze pressure drop and hydrodynamic performance in smooth and segmented baffle pipes across a range of Reynolds numbers in laminar and turbulent flow regimes.
2) The CFD results were validated by comparing to published experimental and analytical results, showing good agreement.
3) Introducing baffles into the pipe was found to increase turbulence, friction, and pressure drop compared to a smooth pipe, as expected based on prior studies of baffled pipes
Diffuser in Steam Vent Silencer By Using Computational Fluid DynamicsIJERA Editor
This document summarizes a research paper that investigated the shape optimization of the pressurized inlet diffuser in a steam vent silencer using computational fluid dynamics (CFD). The researchers analyzed the pressure drop through the silencer with different hole geometries (circular, square, square extrusion) in the inlet diffuser. The results showed that square extrusion geometry had the lowest pressure drop compared to the other geometries. Therefore, the researchers concluded that optimizing the shape of the inlet diffuser to use square extrusion holes can reduce pressure drop in the steam vent silencer.
Experimental studies on pressure drop in a sinusoidal plate heat exchangereSAT Journals
Abstract The corrugated plate heat exchangers are widely used in food and pharmaceutical industries. Sinusoidal plate heat exchangers are one of the types of corrugated plate heat exchanger. Limited research work has been carried out in this type of plate heat exchanger. In the present investigation, experimental studies have been carried out in a sinusoidal corrugated plate heat exchanger with water as the test fluid. The plate heat exchanger is fabricated with two stainless steel sheets having a thickness of 1 mm forming a test channel with a clearance of 5 mm and of length 30cm. 3 such plate heat exchangers have been fabricated with corrugation angles of 30, 40 and 50 degrees. It has been observed from the experimental results that the corrugation angle is mainly affecting the pressure drop and the friction factor. As the corrugation angle is increases, the pressure drop of the fluid is found to increase, which results in decrease in friction factor. These observations have been discussed in the paper. Keywords: sinusoidal plate heat exchanger, corrugation angle, pressure drop, and friction factor
-
Experimental studies on pressure drop in a sinusoidal plate heat exchanger ef...eSAT Publishing House
The document summarizes experimental studies on pressure drop in a sinusoidal plate heat exchanger with varying corrugation angles. Three plate heat exchangers were fabricated with corrugation angles of 30, 40, and 50 degrees. Experiments with water flow showed that pressure drop and friction factor are affected by the corrugation angle. Pressure drop increased linearly with Reynolds number and was highest for the 50 degree angle. Friction factor decreased linearly with Reynolds number on a logarithmic scale and was lowest for the 50 degree angle. The results indicate that higher corrugation angles induce more turbulence, increasing pressure drop but decreasing friction factor.
Experimental Investigation of Heat Transfer Enhancement by Using Clockwise an...ijiert bestjournal
Present Experimental work shows result obtain from experimentation of heat transfer enhancement in
circular horizontal tube by using clockwise and counterclockwise corrugated twisted tape inserts with
working fluid is air. Experiments conducted on plain circular tube with or without c-cc corrugated
twisted tube. During experiment constant heat flux and different mass flow rate condition. The c-cc
corrugated twisted tape are of same pitch and twist ratio but three different angle of rotation in
clockwise and counter clockwise direction as 30˚, 60˚, 90˚ respectively. The Reynolds no. varied from
4000 to 10000. Heat transfer coefficient and pressure drop are calculated and results are compared with
the plain tube without inserts. Finally heat transfer enhances with clockwise and counterclockwise
corrugated twisted tape inserts as compared to plain tube varied from 8 % to 44 % for various inserts.
Plain twisted tape results are also compared with the same results.
Heat Transfer Enhancement using Herringbone wavy & Smooth Wavy fin Heat Excha...IRJET Journal
This document presents a study on heat transfer enhancement using herringbone wavy and smooth wavy fin heat exchangers for hydraulic oil cooling. Two fin configurations - smooth wavy fin and herringbone wavy fin - are experimentally investigated. The performance of two heat exchangers, one with each fin type, are analyzed by passing hot oil through them and studying the cooling effect. Test results show that the smooth wavy fins provide more efficient cooling of hot oil compared to the herringbone fin heat exchanger. Tables of observations recorded during experiments on both heat exchangers are presented.
Experimental Study on Two-Phase Flow in Horizontal Rectangular Minichannel wi...IJERA Editor
An experimental study was conducted to investigate two-phase air-water flow characteristics, in horizontal
rectangular minichannel with Y-junction. The width (W), the height (H) and the hydraulic diameter (DH) of the
rectangular cross section for the upstream side of the junction are 4.60 mm, 2.50 mm and 3.24 mm, while those
for the downstream side are 2.36 mm, 2.50 mm and 2.43 mm. The entire test section was machined from
transparent acrylic block, so that the flow structure could be visualized. Liquid single-phase and air-liquid twophase
flow experiments were conducted at room temperature. The flow pattern, the bubble velocity, the bubble
length, and the void fraction were measured with a high-speed video camera. Pressure profile upstream and
downstream from the junction was also measured for the respective flows, and the pressure loss due to the
contraction at the junction was determined from the pressure profiles. Two flow patterns, i.e., slug and annular
flows, were observed in the fully-developed region apart from the junction. In the analysis, the frictional pressure
drop data, the two-phase frictional multiplier data, bubble velocity data, bubble length data and void fraction data
were compared with calculations by some correlations in literatures. In addition, new pressure loss coefficient
correlations for the pressure drop at the junction has been proposed. Results of such experiment and analysis are
described in the present paper.
A Computational Investigation of Flow Structure Within a Sinuous DuctIJERA Editor
In the present investigation the distribution of mean velocity are experimentally studied on three constant area
rectangular curved ducts with an aspect ratio of 2.4. First one is C-shape, second one is S-shape and third one
is a DS-shape duct. The experiment is carried out at mass averaged mean velocity of 40m/s for all the ducts.
The velocity distribution shows for C-duct, the bulk flow shifting from outer wall to the inner wall along the
flow passage and for S-duct, the bulk flow shifting from outer wall to the inner wall in the first half and from
inner wall to the outer wall in the second half along the flow passage of curved ducts are very instinct. Due to
the imbalance of centrifugal force and radial pressure gradient, secondary motions in the forms of counter
rotating vortices have been generated within both the curved duct. For DS-duct the velocity distributions shows
the Bulk of flow shifting from inner watt to outer wall in the first bend and third bend of the duct and outer wall
to inner wall in the second bend and forth bend of the duct along the flow passage is very instinct. Flow at end
of the DS-duct is purely uniform in nature due to non existence of secondary motion. The experimental results
then were numerically validated with the help of Fluent, which shows a good agreement between the
experimental and predicted results for all the ducts
This document summarizes an experimental study on heat transfer characteristics of a shell and tube heat exchanger using hiTRAN wire matrix turbulators as tube inserts. The study found that using the hiTRAN inserts increased turbulence in the tube side flow, reducing the boundary layer and increasing heat transfer coefficients by 120-130% compared to a plain tube. While the inserts increased pressure drop, the significant increase in heat transfer outweighed this effect. The main applications of hiTRAN inserts are in laminar and transitional flow regimes where they are most effective at enhancing heat transfer, but they can also provide benefits in turbulent flow regimes.
IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE) is an open access international journal that provides rapid publication (within a month) of articles in all areas of mechanical and civil engineering and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in mechanical and civil engineering. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
Density Field Measurements of a Supersonic Impinging Jet with Microjet Controlaswiley1
This document summarizes a study that used background oriented schlieren (BOS) to measure density fields of supersonic impinging jets with and without microjet control. BOS is a technique that uses correlation and topographic algorithms to obtain quantitative density fields with minimal hardware. The study applied BOS to measure density fields of a Mach 1.5 free jet and impinging jet from a converging-diverging nozzle. Microjets placed near the nozzle exit were also used to control the impinging jet, and BOS measured how microjet control affected the density field. Insights from density field measurements could provide a better understanding of flow physics and how microjet control influences shear layer properties of impinging jets.
Heating and-air-conditioning-of-building-faber-and-kell-chapter-14-air-condit...Olumide Daniel
The document discusses air conditioning systems and principles. It defines air conditioning as providing and maintaining a desirable internal atmospheric environment regardless of external conditions. It discusses traditional central plant air conditioning systems that use chilled water, direct expansion cooling coils, and steam or electric heating coils. It also discusses zoned air conditioning systems that divide a building into zones served by separate central plants or floors served by intermediate plant rooms to reduce duct sizes.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Eye sight determination on tablet based hand held device with image processin...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
This document summarizes an experimental study on heat transfer enhancement from surface roughness at laminar flow. Specifically, it examines using circular and oval dimples on an aluminum plate to increase heat transfer from the plate to air flowing over it at Reynolds numbers from 600 to 2000. The study finds that both circular and oval dimples enhance heat transfer compared to a flat plate, while maintaining equivalent or lower pressure drops. The experimental results are validated by comparing the measured Nusselt numbers to theoretical values for a plain vertical plate under laminar flow conditions. In general, the dimpled surfaces increase thermal performance without significantly increasing pressure drops compared to a smooth surface.
The document discusses cyclone technology for removing dust particles from air streams. It provides background on cyclone design parameters like pressure drop and collection efficiency. The optimal dimensions of cyclones are discussed, with the 2D2D design being most efficient for particles larger than 20 microns. While models can predict trends, testing is still needed due to complex flow patterns and many influencing factors. The document also reviews classical cyclone design procedures and limitations of models in accurately predicting performance metrics like number of turns and cut-point diameter.
IRJET- Flow and Heat Transfer Charecterstics of Multiple Jet CoolingIRJET Journal
The document summarizes research on heat transfer characteristics of multiple jet cooling for electronic components. Experiments were conducted using an array of 49 water jets impinging on an electrically heated copper plate. The jet diameter was 0.5mm, arranged in a 7x7 square array with 3mm pitch. Tests were run at flow rates of 22-40 ml/min and heat fluxes of 25-200W/cm2. Results showed that heat transfer coefficient, or Nusselt number, increased with increasing heat flux and Reynolds number. Prior studies on jet impingement cooling are also summarized.
IRJET- Study of Fluid Flow Characteristics for the Flow of Air over a Hea...IRJET Journal
This study examines fluid flow characteristics for air flowing over a heated diamond-shaped tube using computational fluid dynamics (CFD) software. The governing equations for steady, incompressible laminar flow are solved. Pressure drop and friction factor are analyzed for both diamond and circular tubes as the Reynolds number is varied from 438 to 1227. Results show that pressure drop increases and friction factor decreases with Reynolds number for both shapes, though the diamond tube exhibits higher values compared to the circular tube due to its larger frontal area. Velocity distributions also indicate a larger wake region behind the diamond tube. The study aims to provide insights into heat transfer for applications involving cross-flow over tubes such as heat exchangers.
IRJET- Investigation of Fluid Flow Characteristics for the Forced Convect...IRJET Journal
This document summarizes a study that used computational fluid dynamics (CFD) to investigate fluid flow characteristics over heated elliptical and circular shaped tubes. The study varied the Reynolds number from 438 to 1227 and found that elliptical tubes had lower pressure drop and friction factor values than circular tubes. Velocity distributions showed smaller wakes behind elliptical tubes. Pressure drop and friction factor both increased with Reynolds number but elliptical tubes performed better in both areas. The study concluded elliptical tubes provided better heat transfer characteristics than circular tubes of the same hydraulic diameter.
3 ijaems jun-2015-17-comparative pressure drop in laminar and turbulent flowsINFOGAIN PUBLICATION
This document summarizes a study that uses computational fluid dynamics (CFD) to analyze laminar and turbulent flows in circular pipes with and without baffles. It presents the following key points:
1) CFD simulations were conducted using ANSYS Fluent to analyze pressure drop and hydrodynamic performance in smooth and segmented baffle pipes across a range of Reynolds numbers in laminar and turbulent flow regimes.
2) The CFD results were validated by comparing to published experimental and analytical results, showing good agreement.
3) Introducing baffles into the pipe was found to increase turbulence, friction, and pressure drop compared to a smooth pipe, as expected based on prior studies of baffled pipes
Diffuser in Steam Vent Silencer By Using Computational Fluid DynamicsIJERA Editor
This document summarizes a research paper that investigated the shape optimization of the pressurized inlet diffuser in a steam vent silencer using computational fluid dynamics (CFD). The researchers analyzed the pressure drop through the silencer with different hole geometries (circular, square, square extrusion) in the inlet diffuser. The results showed that square extrusion geometry had the lowest pressure drop compared to the other geometries. Therefore, the researchers concluded that optimizing the shape of the inlet diffuser to use square extrusion holes can reduce pressure drop in the steam vent silencer.
Experimental studies on pressure drop in a sinusoidal plate heat exchangereSAT Journals
Abstract The corrugated plate heat exchangers are widely used in food and pharmaceutical industries. Sinusoidal plate heat exchangers are one of the types of corrugated plate heat exchanger. Limited research work has been carried out in this type of plate heat exchanger. In the present investigation, experimental studies have been carried out in a sinusoidal corrugated plate heat exchanger with water as the test fluid. The plate heat exchanger is fabricated with two stainless steel sheets having a thickness of 1 mm forming a test channel with a clearance of 5 mm and of length 30cm. 3 such plate heat exchangers have been fabricated with corrugation angles of 30, 40 and 50 degrees. It has been observed from the experimental results that the corrugation angle is mainly affecting the pressure drop and the friction factor. As the corrugation angle is increases, the pressure drop of the fluid is found to increase, which results in decrease in friction factor. These observations have been discussed in the paper. Keywords: sinusoidal plate heat exchanger, corrugation angle, pressure drop, and friction factor
-
Experimental studies on pressure drop in a sinusoidal plate heat exchanger ef...eSAT Publishing House
The document summarizes experimental studies on pressure drop in a sinusoidal plate heat exchanger with varying corrugation angles. Three plate heat exchangers were fabricated with corrugation angles of 30, 40, and 50 degrees. Experiments with water flow showed that pressure drop and friction factor are affected by the corrugation angle. Pressure drop increased linearly with Reynolds number and was highest for the 50 degree angle. Friction factor decreased linearly with Reynolds number on a logarithmic scale and was lowest for the 50 degree angle. The results indicate that higher corrugation angles induce more turbulence, increasing pressure drop but decreasing friction factor.
Experimental Investigation of Heat Transfer Enhancement by Using Clockwise an...ijiert bestjournal
Present Experimental work shows result obtain from experimentation of heat transfer enhancement in
circular horizontal tube by using clockwise and counterclockwise corrugated twisted tape inserts with
working fluid is air. Experiments conducted on plain circular tube with or without c-cc corrugated
twisted tube. During experiment constant heat flux and different mass flow rate condition. The c-cc
corrugated twisted tape are of same pitch and twist ratio but three different angle of rotation in
clockwise and counter clockwise direction as 30˚, 60˚, 90˚ respectively. The Reynolds no. varied from
4000 to 10000. Heat transfer coefficient and pressure drop are calculated and results are compared with
the plain tube without inserts. Finally heat transfer enhances with clockwise and counterclockwise
corrugated twisted tape inserts as compared to plain tube varied from 8 % to 44 % for various inserts.
Plain twisted tape results are also compared with the same results.
Heat Transfer Enhancement using Herringbone wavy & Smooth Wavy fin Heat Excha...IRJET Journal
This document presents a study on heat transfer enhancement using herringbone wavy and smooth wavy fin heat exchangers for hydraulic oil cooling. Two fin configurations - smooth wavy fin and herringbone wavy fin - are experimentally investigated. The performance of two heat exchangers, one with each fin type, are analyzed by passing hot oil through them and studying the cooling effect. Test results show that the smooth wavy fins provide more efficient cooling of hot oil compared to the herringbone fin heat exchanger. Tables of observations recorded during experiments on both heat exchangers are presented.
Experimental Study on Two-Phase Flow in Horizontal Rectangular Minichannel wi...IJERA Editor
An experimental study was conducted to investigate two-phase air-water flow characteristics, in horizontal
rectangular minichannel with Y-junction. The width (W), the height (H) and the hydraulic diameter (DH) of the
rectangular cross section for the upstream side of the junction are 4.60 mm, 2.50 mm and 3.24 mm, while those
for the downstream side are 2.36 mm, 2.50 mm and 2.43 mm. The entire test section was machined from
transparent acrylic block, so that the flow structure could be visualized. Liquid single-phase and air-liquid twophase
flow experiments were conducted at room temperature. The flow pattern, the bubble velocity, the bubble
length, and the void fraction were measured with a high-speed video camera. Pressure profile upstream and
downstream from the junction was also measured for the respective flows, and the pressure loss due to the
contraction at the junction was determined from the pressure profiles. Two flow patterns, i.e., slug and annular
flows, were observed in the fully-developed region apart from the junction. In the analysis, the frictional pressure
drop data, the two-phase frictional multiplier data, bubble velocity data, bubble length data and void fraction data
were compared with calculations by some correlations in literatures. In addition, new pressure loss coefficient
correlations for the pressure drop at the junction has been proposed. Results of such experiment and analysis are
described in the present paper.
A Computational Investigation of Flow Structure Within a Sinuous DuctIJERA Editor
In the present investigation the distribution of mean velocity are experimentally studied on three constant area
rectangular curved ducts with an aspect ratio of 2.4. First one is C-shape, second one is S-shape and third one
is a DS-shape duct. The experiment is carried out at mass averaged mean velocity of 40m/s for all the ducts.
The velocity distribution shows for C-duct, the bulk flow shifting from outer wall to the inner wall along the
flow passage and for S-duct, the bulk flow shifting from outer wall to the inner wall in the first half and from
inner wall to the outer wall in the second half along the flow passage of curved ducts are very instinct. Due to
the imbalance of centrifugal force and radial pressure gradient, secondary motions in the forms of counter
rotating vortices have been generated within both the curved duct. For DS-duct the velocity distributions shows
the Bulk of flow shifting from inner watt to outer wall in the first bend and third bend of the duct and outer wall
to inner wall in the second bend and forth bend of the duct along the flow passage is very instinct. Flow at end
of the DS-duct is purely uniform in nature due to non existence of secondary motion. The experimental results
then were numerically validated with the help of Fluent, which shows a good agreement between the
experimental and predicted results for all the ducts
This document summarizes an experimental study on heat transfer characteristics of a shell and tube heat exchanger using hiTRAN wire matrix turbulators as tube inserts. The study found that using the hiTRAN inserts increased turbulence in the tube side flow, reducing the boundary layer and increasing heat transfer coefficients by 120-130% compared to a plain tube. While the inserts increased pressure drop, the significant increase in heat transfer outweighed this effect. The main applications of hiTRAN inserts are in laminar and transitional flow regimes where they are most effective at enhancing heat transfer, but they can also provide benefits in turbulent flow regimes.
IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE) is an open access international journal that provides rapid publication (within a month) of articles in all areas of mechanical and civil engineering and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in mechanical and civil engineering. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
Density Field Measurements of a Supersonic Impinging Jet with Microjet Controlaswiley1
This document summarizes a study that used background oriented schlieren (BOS) to measure density fields of supersonic impinging jets with and without microjet control. BOS is a technique that uses correlation and topographic algorithms to obtain quantitative density fields with minimal hardware. The study applied BOS to measure density fields of a Mach 1.5 free jet and impinging jet from a converging-diverging nozzle. Microjets placed near the nozzle exit were also used to control the impinging jet, and BOS measured how microjet control affected the density field. Insights from density field measurements could provide a better understanding of flow physics and how microjet control influences shear layer properties of impinging jets.
Heating and-air-conditioning-of-building-faber-and-kell-chapter-14-air-condit...Olumide Daniel
The document discusses air conditioning systems and principles. It defines air conditioning as providing and maintaining a desirable internal atmospheric environment regardless of external conditions. It discusses traditional central plant air conditioning systems that use chilled water, direct expansion cooling coils, and steam or electric heating coils. It also discusses zoned air conditioning systems that divide a building into zones served by separate central plants or floors served by intermediate plant rooms to reduce duct sizes.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Eye sight determination on tablet based hand held device with image processin...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
A vm scheduling algorithm for reducing power consumption of a virtual machine...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Sentence level sentiment polarity calculation for customer reviews by conside...eSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Arm based human machine interface of plastic extrusion blow molding systemeSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Analysis of multi hop relay algorithm for efficient broadcasting in manetseSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
IRJET- Experimental Investigation of Flow through Perforated Plate in Conical...IRJET Journal
This document describes an experimental investigation of flow through a perforated plate inside a conical diffuser. The goal is to improve the axial flow and achieve higher static pressure rise without total pressure loss. A supersonic wind tunnel was used to test a conical diffuser with an angle of 7 degrees that had two perforated plates placed inside at a distance of 450mm from the inlet. Pressure values were measured using a manometer at various ports and the coefficient of pressure was calculated both without and with the perforated plates. The results found that the addition of the perforated plates improved the flow uniformity and increased the static pressure rise inside the diffuser compared to when no plates were used.
Comparison of cfd simulation of hot and cold fluid mixing in t pipe by placin...eSAT Publishing House
1. The document describes computational fluid dynamics (CFD) simulations of mixing hot and cold water flow in T-pipes with nozzles placed in different locations.
2. The simulations were performed using GAMBIT for geometry modeling and FLUENT software to analyze velocity, temperature, pressure and turbulence contours.
3. Results are presented for four models with the nozzle in different positions, including graphs of flow parameters and mass flow rates at inlets and outlets. The third model placement resulted in the most even mixing and lowest temperatures at the boundaries.
IRJET- Static Pressure Distribution on Plane Flat Plate Surface by Air Or...IRJET Journal
The document presents an experimental study on the static pressure distribution on a flat plate surface due to air jet impingement from a circular orifice. Key findings from the study include:
1) The static pressure coefficient (Cp) is highest at the stagnation point where the jet first impinges on the plate (x/d = 0) and decreases with increasing longitudinal distance (x/d) from the impingement point.
2) Cp values decrease with increasing nozzle to plate distance (Z/d) as the jet spreads over a larger surface area.
3) Within the range of Reynolds numbers studied (6000-40000), Reynolds number does not influence the static pressure distribution.
This document summarizes the design optimization and analysis of an impeller for a centrifugal compressor. It begins with background on centrifugal compressors and their applications. The aim is then stated as developing a methodology to design a centrifugal compressor impeller accounting for real fluid effects. A computer program is developed based on jet-wake theory to estimate impeller dimensions. The methodology is validated by comparing results to an existing impeller design, showing encouraging accuracy. The method is then applied to design an impeller for an air conditioning system using R-12 as the refrigerant at 18,000 rpm. Key design parameters are examined at varying speeds to select optimal values.
An Investigation on the Performance Characteristics of a Centrifugal CompressorIJERD Editor
The design and off-design performance characteristics of single stage centrifugal compressor
consisting of 12 vanes impeller interfacing with 11 vanes diffuser have been studied experimentally and
numerically. The impeller has been designed and developed with radial exit, 30o inlet blade angle (with
tangent), 77 mm diameter and the discharge volute considering constant mean flow velocity. The performance
of the compressor at varying capacity (60 to 120 % of design) by controlling the discharge valve and with the
variation of rotating speed (15000 to 35000 rpm) by regulating speed of the coupled gas turbine has been
conducted at the recently developed test rig. The numerical simulation has been done by adopting viscous
Reynolds Average Navier-Stokes (RANS) equations with and without Coriolis Force & Centrifugal Force in
rotating reference frame (impeller) and stationary reference frame (casing) respectively utilizing CFD software
Fluent 14. The flow around a single vane of impeller interfacing with single vane of diffuser, the rotational
periodicity and sliding mesh at the interfacing zone between rotating impeller and stationery diffuser are
considered. Non dimensional performance curves derived from experimental and numerical results are
presented and compared. The numerical results are found to match very closely with the experimented data near
the design point and deviation is observed at the both side of the designed operating point. Non-uniform
pressure profiles towards the impeller exit and strong cross flow from blade to blade are detected at low flow
operating conditions. Total pressure, static pressure and velocity distributions at design and off design
operation obtained from the CFD results are analysed and presented here.
Experimental Investigations and Computational Analysis on Subsonic Wind Tunnelijtsrd
This paper disclose the entire approach to design an open circuit subsonic wind tunnel which will be used to consider the wind impact on the airfoil. The current rules and discoveries of the past research works were sought after for plan figuring of different segments of the wind tunnel. Wind speed of 26 m s have been practiced at the test territory. The wind qualities over a symmetrical airfoil are viewed as probably in a low speed wind tunnel. Tests were finished by moving the approach, from 0 to 5 degree. The stream attributes over a symmetrical airfoil are examined tentatively. The pressure distribution on the airfoil area was estimated, lift and drag force were estimated and velocity profiles were acquired. Rishabh Kumar Sahu | Saurabh Sharma | Vivek Swaroop | Vishal Kumar ""Experimental Investigations and Computational Analysis on Subsonic Wind Tunnel"" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-3 , April 2019, URL: https://www.ijtsrd.com/papers/ijtsrd23511.pdf
Paper URL: https://www.ijtsrd.com/engineering/mechanical-engineering/23511/experimental-investigations-and-computational-analysis-on-subsonic-wind-tunnel/rishabh-kumar-sahu
Effect of tip clearance on performance of a centrifugal compressoreSAT Journals
Abstract The centrifugal compressor is to study the effect of tip clearance on the performance characteristics and the wall static pressure for a different flow co-efficient. The method of testing the compressor is run at a constant speed at 2000rpm. The tip clearance is varied by using spacers. The volume flow rate is varied with the help of throttling device to conduct the performance test. The performance characteristic of the centrifugal compressor showing the variation of discharge pressure with volume flow rate is plotted. Obtaining the performance characteristics showing the variation of discharge pressure with volume flow rate for different tip clearance, viz. =2.2%, 4%, 6.1% and 7.9%. Measurement of periodic pressure at various tip clearance viz. =2.2%, 4%, 6.1% and 7.9%. For each tip clearance pressure measured in radial location of impeller at 6 positions for different flow co efficient values. Five flow coefficients viz., ф =0.40, =0.34 (both above design flow), =0.28 (near design flow), =0.21=0.18 (both below design flow) and four values of non-dimensional tip clearance viz., =2.2%, 4%, 6.1% and 7.9%, are chosen for experimental work. The objective of the research work is to measure the periodic variation static pressure on the casing over the rotor at different values of tip clearance and flow coefficients. With the availability of these data, it is possible to improve the tip clearance flow in centrifugal compressor.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Cfd simulation of single stage axial flow compressor for varying blade aspect...eSAT Journals
Abstract The aspect ratio of blade is an important parameter and has a strong influence on the performance of axial flow compressor. The performance of axial flow compressors is known to be affected by the choice of aspect ratio (the ratio of blade height to axial chord length). A study has been carried out to verify the effect of aspect ratio on the performance of 1.2 pressure ratio single stage subsonic compressor through AxStream analysis using Axial flow compressor design. The analysis has been carried out for the constant tip diameter of the compressor rotor blade having an aspect ratio 1, 2 and 3 and obtained the pressure loss and flow parameters of the compressor stage. This paper shows that the best operating conditions occur for the aspect ratio between 2 and 3. Keywords: Axial flow compressor, Aspect ratio, Computational Fluid Dynamic, AxStream
Influence of number of impeller and diffuser blades on the pressure recovery ...eSAT Journals
This document summarizes a numerical analysis that investigated the influence of the number of impeller and diffuser blades on the pressure recovery of a centrifugal fan. The analysis found that higher numbers of impeller blades (up to 14 blades) resulted in better pressure recovery due to improved blade loading. Additionally, a smaller number of diffuser blades (12 blades) produced higher pressure recovery by avoiding flow separation and stall near the blades. In general, the analysis showed that configurations with more impeller blades and fewer diffuser blades achieved better static pressure recovery and lower total pressure losses across the fan.
This document summarizes a study that used computational fluid dynamics (CFD) to simulate the performance of a single-stage axial flow compressor with varying blade aspect ratios of 1, 2, and 3. The study found that compressor performance is affected by aspect ratio, with the best operating conditions occurring between ratios of 2 and 3. Streamline analyses were conducted to analyze pressure and velocity distributions within the compressor and determine how parameters like mach number varied across different aspect ratio configurations. Modal analyses were also performed to study frequency responses at different vibration modes.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Designing and installation of low cost optimized wind monitoring systemeSAT Publishing House
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology.
Experimental investigation of air flow characteristics in rectangular channel...eSAT Journals
Abstract This experimental study is to investigate the effect or influence of pedestal vortex generator on one wall of rectangular duct on the flow performance. The effects of geometrical parameters of pedestal vortex generator and aspect ratio of duct on friction factor ratio have resulted in Reynolds number which is based on hydraulic diameter of the rectangular channel in the range 8000 to 24000. The factors which are varied for vortex generator were pitch to height ratio of vortex generator (p/h) and aspect ratios of vortex generators (Δ). Vortex generator numbers were also varied on wall at axial locations. Experimental results reported for aspect ratio 2.8, 5.5, 7.3 and 1.6 of pedestal vortex generator and pitch to height ratio (P/h) 4,8,12, 16. And 8000 to 24000 is the range of Reynolds number. Experimentally investigated that the friction factor ratio increases with increase in Reynolds number and friction factor ratio increases with decrease in pitch to height ratio. For pedestal vortex generator with aspect ratio 2.8 and height 8mm the results were, For pitch to height ratio (P/h)=16 friction factor ratio for 8000 Reynolds number is 27.12% less than the friction factor ratio for the Reynolds number 24000. So it is clear that friction factor ratio increases with increase in Reynolds number. And for Reynolds number 20000, pitch to height ratio (P/h) =4 friction factor ratio is 21.14% greater than pitch to height ratio (P/h)=16 so we can say that friction factor ratio increases with decrease in pitch to height ratio. Keywords: Pitch to height ratio, Aspect ratio, Pressure drop, Hydraulic diameter, Pedestals
This document describes different flow measurement devices including the venturi meter, orifice plate, and rotameter. It provides details on how each device works based on pressure differences caused by a flow restriction. The objectives are to study and compare the characteristics of venturi meters and orifice plates, calculate flow rates using measured pressure drops, and understand how rotameters operate based on the position of a float. An apparatus is described that can be used to collect pressure and flow rate data from each device to analyze flow measurement principles.
IRJET - Characteristics of 90°/90° S-Shaped Diffusing Duct using SST K-O Turb...IRJET Journal
1) The document summarizes a study that uses computational fluid dynamics (CFD) to analyze the characteristics of a 90/90 S-shaped diffusing duct.
2) The study explores the velocity variation, pressure recovery coefficient, and total pressure loss coefficient along the duct using the SST k-ω turbulent model.
3) The results show flow separation near the top and bottom walls, the formation of counter-rotating vortex pairs at the exit, and that the pressure recovery coefficient first increases then decreases before increasing again towards the exit.
Optimization of design of mixed flow centrifugal pump impeller using cfdeSAT Journals
Abstract
Centrifugal pumps are widely used hydraulic machines, irrespective of the fact that their performance is generally not very good. So, turning them into more efficient machines is quite a challenge. The performance of a centrifugal pump is highly dependent on its geometrical parameters and its vane profile. In order to analyze the flow through complex systems like centrifugal pumps, Computation fluid dynamics (CFD) has been used. This work aims to study the performance analysis of a centrifugal mixed flow pump designed to deliver 0.25 m3/s of water with a head of 20 m at a speed of 1450 rpm using ANSYS CFX (ver.14.0). PTC Creo (ver. 2.0) has been used to model the pump unit. The performance of the pump was first determined using the existing vane angles and thickness of the blade then, the inlet vane angle, the outlet vane angle along with the thickness of the blade has been varied to analyze the pump’s performance . The results show that for an initial inlet angle 21.08˚, outlet angle 16.28˚ and blade thickness as 10mm, the efficiency of the pump was 84%. However, the efficiency of pump rises to 89.19% for the optimized angles and blade thickness.
Optimization of design of mixed flow centrifugal pump impeller using cfdeSAT Journals
Abstract
Centrifugal pumps are widely used hydraulic machines, irrespective of the fact that their performance is generally not very good. So, turning them into more efficient machines is quite a challenge. The performance of a centrifugal pump is highly dependent on its geometrical parameters and its vane profile. In order to analyze the flow through complex systems like centrifugal pumps, Computation fluid dynamics (CFD) has been used. This work aims to study the performance analysis of a centrifugal mixed flow pump designed to deliver 0.25 m3/s of water with a head of 20 m at a speed of 1450 rpm using ANSYS CFX (ver.14.0). PTC Creo (ver. 2.0) has been used to model the pump unit. The performance of the pump was first determined using the existing vane angles and thickness of the blade then, the inlet vane angle, the outlet vane angle along with the thickness of the blade has been varied to analyze the pump’s performance . The results show that for an initial inlet angle 21.08˚, outlet angle 16.28˚ and blade thickness as 10mm, the efficiency of the pump was 84%. However, the efficiency of pump rises to 89.19% for the optimized angles and blade thickness.
Keywords: Computational Fluid Dynamics (CFD) Analysis, Mixed Flow Pump, Overall Efficiency.
This document summarizes an analysis of the fatigue life of a tubesheet used in an industrial filtration system. The analysis involved:
1) Calculating the dimensions of the tubesheet based on client specifications.
2) Performing static and transient dynamic finite element analyses to determine stress and deformation values under different loading conditions.
3) Using the stress and deformation results to predict the fatigue life of the tubesheet according to ASME codes.
4) Validating the FEA results by comparing predicted and measured deformation values from an actual hydrotest.
The analysis found that the tubesheet could withstand the alternating stresses from the filtration process cycles for an infinite fatigue life.
IRJET- Design, Fabrication and Testing of a Small Scale Low Reynolds Number T...IRJET Journal
This document summarizes the design, fabrication, and testing of a small-scale, low Reynolds number table top wind tunnel. The wind tunnel is an open circuit design with a 1.8m length and a square test section intended to achieve flow velocities of around 8m/s. Components of the wind tunnel like the contraction nozzle, diffuser, and settling chamber were designed and fabricated from mild steel. Computational fluid dynamics simulations were performed to analyze the flow characteristics. The designed wind tunnel was then calibrated by measuring test section velocities using a pitot-static probe at various fan speeds. The wind tunnel is intended to study aerodynamic characteristics of UAVs and MAVs that fly at low speeds.
Similar to Wall static pressure distribution due to confined impinging circular air jet (20)
Hudhud cyclone caused extensive damage in Visakhapatnam, India in October 2014, especially to tree cover. This will likely impact the local environment in several ways: increased air pollution as trees absorb less; higher temperatures without tree canopy; increased erosion and landslides. It also created large amounts of waste from destroyed trees. Proper management of solid waste is needed to prevent disease spread. Suggested measures include restoring damaged plants, building fountains to reduce heat, mandating light-colored buildings, improving waste management, and educating public on health risks. Overall, changes are needed to water, land, and waste practices to rebuild the environment after the cyclone removed green cover.
Impact of flood disaster in a drought prone area – case study of alampur vill...eSAT Publishing House
1) In September-October 2009, unprecedented heavy rainfall and dam releases caused widespread flooding in Alampur village in Mahabub Nagar district, a historically drought-prone area.
2) The flood damaged or destroyed homes, buildings, infrastructure, crops, and documents. It displaced many residents and cut off the village.
3) The socioeconomic conditions and mud-based construction of homes in the village exacerbated the flood's impacts, making damage more severe and recovery more difficult.
The document summarizes the Hudhud cyclone that struck Visakhapatnam, India in October 2014. It describes the cyclone's formation, rapid intensification to winds of 175 km/h, and landfall near Visakhapatnam. The cyclone caused extensive damage estimated at over $1 billion and at least 109 deaths in India and Nepal. Infrastructure like buildings, bridges, and power lines were destroyed. Crops and fishing boats were also damaged. The document then discusses coping strategies and improvements needed to disaster management plans to better prepare for future cyclones.
Groundwater investigation using geophysical methods a case study of pydibhim...eSAT Publishing House
This document summarizes the results of a geophysical investigation using vertical electrical sounding (VES) methods at 13 locations around an industrial area in India. The VES data was interpreted to generate geo-electric sections and pseudo-sections showing subsurface resistivity variations. Three main layers were typically identified - a high resistivity topsoil, a weathered middle layer, and a basement rock. Pseudo-sections revealed relatively more weathered areas in the northwest and southwest. Resistivity sections helped identify zones of possible high groundwater potential based on low resistivity anomalies sandwiched between more resistive layers. The study concluded the electrical resistivity method was useful for understanding subsurface geology and identifying areas prospective for groundwater exploration.
Flood related disasters concerned to urban flooding in bangalore, indiaeSAT Publishing House
1. The document discusses urban flooding in Bangalore, India. It describes how factors like heavy rainfall, population growth, and improper land use have contributed to increased flooding in the city.
2. Flooding events in 2013 are analyzed in detail. A November rainfall caused runoff six times higher than the drainage capacity, inundating low-lying residential areas.
3. Impacts of urban flooding include disrupted daily life, damaged infrastructure, and decreased economic activity in affected areas. The document calls for improved flood management strategies to better mitigate urban flooding risks in Bangalore.
Enhancing post disaster recovery by optimal infrastructure capacity buildingeSAT Publishing House
This document discusses enhancing post-disaster recovery through optimal infrastructure capacity building. It presents a model to minimize the cost of meeting demand using auxiliary capacities when disaster damages infrastructure. The model uses genetic algorithms to select optimal capacity combinations. The document reviews how infrastructure provides vital services supporting recovery activities and discusses classifying infrastructure into six types. When disaster reduces infrastructure services, a gap forms between community demands and available support, hindering recovery. The proposed research aims to identify this gap and optimize capacity selection to fill it cost-effectively.
Effect of lintel and lintel band on the global performance of reinforced conc...eSAT Publishing House
This document analyzes the effect of lintels and lintel bands on the seismic performance of reinforced concrete masonry infilled frames through non-linear static pushover analysis. Four frame models are considered: a frame with a full masonry infill wall; a frame with a central opening but no lintel/band; a frame with a lintel above the opening; and a frame with a lintel band above the opening. The results show that the full infill wall model has 27% higher stiffness and 32% higher strength than the model with just an opening. Models with lintels or lintel bands have slightly higher strength and stiffness than the model with just an opening. The document concludes lintels and lintel
Wind damage to trees in the gitam university campus at visakhapatnam by cyclo...eSAT Publishing House
1) A cyclone with wind speeds of 175-200 kph caused massive damage to the green cover of Gitam University campus in Visakhapatnam, India. Thousands of trees were uprooted or damaged.
2) A study assessed different types of damage to trees from the cyclone, including defoliation, salt spray damage, damage to stems/branches, and uprooting. Certain tree species were more vulnerable than others.
3) The results of the study can help in selecting more wind-resistant tree species for future planting and reducing damage from future storms.
Wind damage to buildings, infrastrucuture and landscape elements along the be...eSAT Publishing House
1) A visual study was conducted to assess wind damage from Cyclone Hudhud along the 27km Visakha-Bheemli Beach road in Visakhapatnam, India.
2) Residential and commercial buildings suffered extensive roof damage, while glass facades on hotels and restaurants were shattered. Infrastructure like electricity poles and bus shelters were destroyed.
3) Landscape elements faced damage, including collapsed trees that damaged pavements, and debris in parks. The cyclone wiped out over half the city's green cover and caused beach erosion around protected areas.
1) The document reviews factors that influence the shear strength of reinforced concrete deep beams, including compressive strength of concrete, percentage of tension reinforcement, vertical and horizontal web reinforcement, aggregate interlock, shear span-to-depth ratio, loading distribution, side cover, and beam depth.
2) It finds that compressive strength of concrete, tension reinforcement percentage, and web reinforcement all increase shear strength, while shear strength decreases as shear span-to-depth ratio increases.
3) The distribution and amount of vertical and horizontal web reinforcement also affects shear strength, but closely spaced stirrups do not necessarily enhance capacity or performance.
Role of voluntary teams of professional engineers in dissater management – ex...eSAT Publishing House
1) A team of 17 professional engineers from various disciplines called the "Griha Seva" team volunteered after the 2001 Gujarat earthquake to provide technical assistance.
2) The team conducted site visits, assessments, testing and recommended retrofitting strategies for damaged structures in Bhuj and Ahmedabad. They were able to fully assess and retrofit 20 buildings in Ahmedabad.
3) Factors observed that exacerbated the earthquake's impacts included unplanned construction, non-engineered buildings, improper prior retrofitting, and defective materials and workmanship. The professional engineers' technical expertise was crucial for effective post-disaster management.
This document discusses risk analysis and environmental hazard management. It begins by defining risk, hazard, and toxicity. It then outlines the steps involved in hazard identification, including HAZID, HAZOP, and HAZAN. The document presents a case study of a hypothetical gas collecting station, identifying potential accidents and hazards. It discusses quantitative and qualitative approaches to risk analysis, including calculating a fire and explosion index. The document concludes by discussing hazard management strategies like preventative measures, control measures, fire protection, relief operations, and the importance of training personnel on safety.
Review study on performance of seismically tested repaired shear wallseSAT Publishing House
This document summarizes research on the performance of reinforced concrete shear walls that have been repaired after damage. It begins with an introduction to shear walls and their failure modes. The literature review then discusses the behavior of original shear walls as well as different repair techniques tested by other researchers, including conventional repair with new concrete, jacketing with steel plates or concrete, and use of fiber reinforced polymers. The document focuses on evaluating the strength retention of shear walls after being repaired with various methods.
Monitoring and assessment of air quality with reference to dust particles (pm...eSAT Publishing House
This document summarizes a study on monitoring and assessing air quality with respect to dust particles (PM10 and PM2.5) in the urban environment of Visakhapatnam, India. Sampling was conducted in residential, commercial, and industrial areas from October 2013 to August 2014. The average PM2.5 and PM10 concentrations were within limits in residential areas but moderate to high in commercial and industrial areas. Exceedance factor levels indicated moderate pollution for residential areas and moderate to high pollution for commercial and industrial areas. There is a need for management measures like improved public transport and green spaces to combat particulate air pollution in the study areas.
Low cost wireless sensor networks and smartphone applications for disaster ma...eSAT Publishing House
This document describes a low-cost wireless sensor network and smartphone application system for disaster management. The system uses an Arduino-based wireless sensor network comprising nodes with various sensors to monitor the environment. The sensor data is transmitted to a central gateway and then to the cloud for analysis. A smartphone app connected to the cloud can detect disasters from the sensor data and send real-time alerts to users to help with early evacuation. The system aims to provide low-cost localized disaster detection and warnings to improve safety.
Coastal zones – seismic vulnerability an analysis from east coast of indiaeSAT Publishing House
This document summarizes an analysis of seismic vulnerability along the east coast of India. It discusses the geotectonic setting of the region as a passive continental margin and reports some moderate seismic activity from offshore in recent decades. While seismic stability cannot be assumed given events like the 2004 tsunami, no major earthquakes have been recorded along this coast historically. The document calls for further study of active faults, neotectonics, and implementation of improved seismic building codes to mitigate vulnerability.
Can fracture mechanics predict damage due disaster of structureseSAT Publishing House
This document discusses how fracture mechanics can be used to better predict damage and failure of structures. It notes that current design codes are based on small-scale laboratory tests and do not account for size effects, which can lead to more brittle failures in larger structures. The document outlines how fracture mechanics considers factors like size effect, ductility, and minimum reinforcement that influence the strength and failure behavior of structures. It provides examples of how fracture mechanics has been applied to problems like evaluating shear strength in deep beams and investigating a failure of an oil platform structure. The document argues that fracture mechanics provides a more scientific basis for structural design compared to existing empirical code provisions.
This document discusses the assessment of seismic susceptibility of reinforced concrete (RC) buildings. It begins with an introduction to earthquakes and the importance of vulnerability assessment in mitigating earthquake risks and losses. It then describes modeling the nonlinear behavior of RC building elements and performing pushover analysis to evaluate building performance. The document outlines modeling RC frames and developing moment-curvature relationships. It also summarizes the results of pushover analyses on sample 2D and 3D RC frames with and without shear walls. The conclusions emphasize that pushover analysis effectively assesses building properties but has limitations, and that capacity spectrum method provides appropriate results for evaluating building response and retrofitting impact.
A geophysical insight of earthquake occurred on 21 st may 2014 off paradip, b...eSAT Publishing House
1) A 6.0 magnitude earthquake occurred off the coast of Paradip, Odisha in the Bay of Bengal on May 21, 2014 at a depth of around 40 km.
2) Analysis of magnetic and bathymetric data from the area revealed the presence of major lineaments in NW-SE and NE-SW directions that may be responsible for seismic activity through stress release.
3) Movements along growth faults at the margins of large Bengal channels, due to large sediment loads, could also contribute to seismic events by triggering movements along the faults.
Effect of hudhud cyclone on the development of visakhapatnam as smart and gre...eSAT Publishing House
This document discusses the effects of Cyclone Hudhud on the development of Visakhapatnam as a smart and green city through a case study and preliminary surveys. The surveys found that 31% of participants had experienced cyclones, 9% floods, and 59% landslides previously in Visakhapatnam. Awareness of disaster alarming systems increased from 14% before the 2004 tsunami to 85% during Cyclone Hudhud, while awareness of disaster management systems increased from 50% before the tsunami to 94% during Hudhud. The surveys indicate that initiatives after the tsunami improved awareness and preparedness. Developing Visakhapatnam as a smart, green city should consider governance
Open Channel Flow: fluid flow with a free surfaceIndrajeet sahu
Open Channel Flow: This topic focuses on fluid flow with a free surface, such as in rivers, canals, and drainage ditches. Key concepts include the classification of flow types (steady vs. unsteady, uniform vs. non-uniform), hydraulic radius, flow resistance, Manning's equation, critical flow conditions, and energy and momentum principles. It also covers flow measurement techniques, gradually varied flow analysis, and the design of open channels. Understanding these principles is vital for effective water resource management and engineering applications.
Null Bangalore | Pentesters Approach to AWS IAMDivyanshu
#Abstract:
- Learn more about the real-world methods for auditing AWS IAM (Identity and Access Management) as a pentester. So let us proceed with a brief discussion of IAM as well as some typical misconfigurations and their potential exploits in order to reinforce the understanding of IAM security best practices.
- Gain actionable insights into AWS IAM policies and roles, using hands on approach.
#Prerequisites:
- Basic understanding of AWS services and architecture
- Familiarity with cloud security concepts
- Experience using the AWS Management Console or AWS CLI.
- For hands on lab create account on [killercoda.com](https://killercoda.com/cloudsecurity-scenario/)
# Scenario Covered:
- Basics of IAM in AWS
- Implementing IAM Policies with Least Privilege to Manage S3 Bucket
- Objective: Create an S3 bucket with least privilege IAM policy and validate access.
- Steps:
- Create S3 bucket.
- Attach least privilege policy to IAM user.
- Validate access.
- Exploiting IAM PassRole Misconfiguration
-Allows a user to pass a specific IAM role to an AWS service (ec2), typically used for service access delegation. Then exploit PassRole Misconfiguration granting unauthorized access to sensitive resources.
- Objective: Demonstrate how a PassRole misconfiguration can grant unauthorized access.
- Steps:
- Allow user to pass IAM role to EC2.
- Exploit misconfiguration for unauthorized access.
- Access sensitive resources.
- Exploiting IAM AssumeRole Misconfiguration with Overly Permissive Role
- An overly permissive IAM role configuration can lead to privilege escalation by creating a role with administrative privileges and allow a user to assume this role.
- Objective: Show how overly permissive IAM roles can lead to privilege escalation.
- Steps:
- Create role with administrative privileges.
- Allow user to assume the role.
- Perform administrative actions.
- Differentiation between PassRole vs AssumeRole
Try at [killercoda.com](https://killercoda.com/cloudsecurity-scenario/)
Build the Next Generation of Apps with the Einstein 1 Platform.
Rejoignez Philippe Ozil pour une session de workshops qui vous guidera à travers les détails de la plateforme Einstein 1, l'importance des données pour la création d'applications d'intelligence artificielle et les différents outils et technologies que Salesforce propose pour vous apporter tous les bénéfices de l'IA.
Supermarket Management System Project Report.pdfKamal Acharya
Supermarket management is a stand-alone J2EE using Eclipse Juno program.
This project contains all the necessary required information about maintaining
the supermarket billing system.
The core idea of this project to minimize the paper work and centralize the
data. Here all the communication is taken in secure manner. That is, in this
application the information will be stored in client itself. For further security the
data base is stored in the back-end oracle and so no intruders can access it.
Tools & Techniques for Commissioning and Maintaining PV Systems W-Animations ...Transcat
Join us for this solutions-based webinar on the tools and techniques for commissioning and maintaining PV Systems. In this session, we'll review the process of building and maintaining a solar array, starting with installation and commissioning, then reviewing operations and maintenance of the system. This course will review insulation resistance testing, I-V curve testing, earth-bond continuity, ground resistance testing, performance tests, visual inspections, ground and arc fault testing procedures, and power quality analysis.
Fluke Solar Application Specialist Will White is presenting on this engaging topic:
Will has worked in the renewable energy industry since 2005, first as an installer for a small east coast solar integrator before adding sales, design, and project management to his skillset. In 2022, Will joined Fluke as a solar application specialist, where he supports their renewable energy testing equipment like IV-curve tracers, electrical meters, and thermal imaging cameras. Experienced in wind power, solar thermal, energy storage, and all scales of PV, Will has primarily focused on residential and small commercial systems. He is passionate about implementing high-quality, code-compliant installation techniques.
Prediction of Electrical Energy Efficiency Using Information on Consumer's Ac...PriyankaKilaniya
Energy efficiency has been important since the latter part of the last century. The main object of this survey is to determine the energy efficiency knowledge among consumers. Two separate districts in Bangladesh are selected to conduct the survey on households and showrooms about the energy and seller also. The survey uses the data to find some regression equations from which it is easy to predict energy efficiency knowledge. The data is analyzed and calculated based on five important criteria. The initial target was to find some factors that help predict a person's energy efficiency knowledge. From the survey, it is found that the energy efficiency awareness among the people of our country is very low. Relationships between household energy use behaviors are estimated using a unique dataset of about 40 households and 20 showrooms in Bangladesh's Chapainawabganj and Bagerhat districts. Knowledge of energy consumption and energy efficiency technology options is found to be associated with household use of energy conservation practices. Household characteristics also influence household energy use behavior. Younger household cohorts are more likely to adopt energy-efficient technologies and energy conservation practices and place primary importance on energy saving for environmental reasons. Education also influences attitudes toward energy conservation in Bangladesh. Low-education households indicate they primarily save electricity for the environment while high-education households indicate they are motivated by environmental concerns.
Impartiality as per ISO /IEC 17025:2017 StandardMuhammadJazib15
This document provides basic guidelines for imparitallity requirement of ISO 17025. It defines in detial how it is met and wiudhwdih jdhsjdhwudjwkdbjwkdddddddddddkkkkkkkkkkkkkkkkkkkkkkkwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwioiiiiiiiiiiiii uwwwwwwwwwwwwwwwwhe wiqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq gbbbbbbbbbbbbb owdjjjjjjjjjjjjjjjjjjjj widhi owqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq uwdhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhwqiiiiiiiiiiiiiiiiiiiiiiiiiiiiw0pooooojjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjj whhhhhhhhhhh wheeeeeeee wihieiiiiii wihe
e qqqqqqqqqqeuwiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiqw dddddddddd cccccccccccccccv s w c r
cdf cb bicbsad ishd d qwkbdwiur e wetwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww w
dddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddfffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffw
uuuuhhhhhhhhhhhhhhhhhhhhhhhhe qiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii iqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqqccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc ccccccccccccccccccccccccccccccccccc bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbu uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuum
m
m mmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm m i
g i dijsd sjdnsjd ndjajsdnnsa adjdnawddddddddddddd uw
This study Examines the Effectiveness of Talent Procurement through the Imple...DharmaBanothu
In the world with high technology and fast
forward mindset recruiters are walking/showing interest
towards E-Recruitment. Present most of the HRs of
many companies are choosing E-Recruitment as the best
choice for recruitment. E-Recruitment is being done
through many online platforms like Linkedin, Naukri,
Instagram , Facebook etc. Now with high technology E-
Recruitment has gone through next level by using
Artificial Intelligence too.
Key Words : Talent Management, Talent Acquisition , E-
Recruitment , Artificial Intelligence Introduction
Effectiveness of Talent Acquisition through E-
Recruitment in this topic we will discuss about 4important
and interlinked topics which are
This study Examines the Effectiveness of Talent Procurement through the Imple...
Wall static pressure distribution due to confined impinging circular air jet
1. IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
__________________________________________________________________________________________
Volume: 03 Special Issue: 03 | May-2014 | NCRIET-2014, Available @ http://www.ijret.org 591
WALL STATIC PRESSURE DISTRIBUTION DUE TO CONFINED
IMPINGING CIRCULAR AIR JET
Patil Deogonda1
, Vijaykumar N Chalwa2
, Murugesh M.C3
, Vinod Dixit4
1Assistance Professor, Dept of Mechanical Engineering. SMSMPITR, Akluj
2
Dean R&D, Dept. of Mechanical Engineering, SMSMPITR, Akluj
3
Assistance professor, Dept. of Mechanical Engineering. G.M.I.T, Davangere
4
Design engineer Zuti Engg. Pvt.Ltd. Hyderabad
The wall static pressure of confined air jet, impinging normally onto a flat plate has been experimentally investigated. The mean
velocities, and wall static pressures were measured for Reynolds numbers ranging from 18,000 to 40,000 and the nozzle-to-plate
spacing’s in range of 0.25–4. The effects of Reynolds number, nozzle-to-plate spacing and flow confinement on the pressure
coefficient are reported. The pressure distributions are independent of the Reynolds number and depend on nozzle-to-plate spacing
only. The maximum pressure occurs at the stagnation point (r/d=0) for the all nozzle-to-plate spacing’s studied and as r/d increases,
the pressure decreases. At very low spacing (z/d=0.25) stagnation pressure is rather larger than those of the other spacing’s due to
rapidly decreasing of axial velocity in the deflection zone. It is concluded that a sub atmospheric region occurs on the impingement
plate for the nozzle-to-plate spacing’s up to one for all the Reynolds number; however, there is no evidence of the sub atmospheric
region in confined jet For the nozzle-to-plate spacing’s greater than one.
---------------------------------------------------------------------***---------------------------------------------------------------------
1. INTRODUCTION
Impinging jets are used in many industrial applications to
achieve enhanced coefficients for convective heating, cooling
or drying. Applications include tempering of glass plate,
annealing of metal sheets, drying of textile and paper products,
deicing of aircraft systems and cooling of heated components
in gas turbine engines, Computers and electronic instruments.
The flow and heat transfer characteristics of an impinging jet
are affected from a number of parameters such as the nozzle
geometry, the nozzle-to-plate spacing (H/D), and Reynolds
number.
The impinging jets can be classified by their boundary as
confined flow field. Confined geometry, where the radial
spread of the jet is bounded by a confinement plate, has been
investigated extensively in literature due to its importance in
industrial applications.
1.1 Structure of Free Jet
The structure of free jet is as shown in the Fig. 1.a. The three
zones of the free jet are
a) Potential core zone
b) Developing zone
c) Developed zone
The jet immediately leaving the nozzle comes in contact with
surrounding stagnant air. The free shearing between moving
jet and stagnant air causes the mixing due to which fluid
particles of the surrounding air are carried with the jet, which
causes the sharing of the momentum of the jet and formation
of the shear layer. Within the shear layer there exists a flow of
jet which is still unaffected by mixing and its velocity is same
as the nozzle exit velocity. This zone is potential core of the
jet.
Fig.-1. Impinging jet
In the potential core zone, the centerline velocity of the jet
remains constant and is equal to the nozzle exit velocity. The
end of the potential core is defined as the axial distance from
the nozzle exit up to the point where the jet velocity is 0.95
times the nozzle exit velocity (Jambunathan et al., 1992).
Typical length of the potential core is found to be 6-7 times
the nozzle diameter for the axis-symmetric jet and 4.7 -7.7
2. IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
__________________________________________________________________________________________
Volume: 03 Special Issue: 03 | May-2014 | NCRIET-2014, Available @ http://www.ijret.org 592
times the slot width for two dimensional jets (Viskanta, 1993).
However, this length depends on nozzle geometry and
turbulent intensity in the nozzle exit and initial velocity
profile. In the developing zone, due to large shear stresses at
the jet boundary, axial velocity profile decays. In the
developed zone the velocity profile is fully developed and the
jet broadens linearly along with linear decay of axial velocity.
1.2 Structure of Impinging Jet
Fig.-2. Impinging jet
Unconfined jet impingement system is one in which jet after
impingement on a surface is exited without confinement.
Figure 1.5b shows the flow field of an impinging jet on to an
orthogonal plate. The flow structures of impinging axi-
symmetric jet can be subdivided into three characteristic
regions.
1. The free jet region
2. The stagnation flow region
3. The wall jet region.
2. EXPERIMENTAL SET UP
Fig-3.shows a schematic of the experimental apparatus. Air is
discharged from a long pipe nozzle which is mounted with its
axis horizontal in the center of a confined plate. The air is
supplied to the nozzle by means of a centrifugal blower
mounted beside the confined plate. The air flow is regulated
by a valve. The nozzle is 16.5 mm diameter and 750 mm
length, of which outlet is slightly rounded. The impingement
plate made of Plexiglas with area of 250 mm2
and 10 mm
thickness, and it is mounted perpendicular to the jet axis. The
jet issuing from the nozzle, with a velocity U0, impinges onto
the impingement plate at a distance H from the nozzle and
enters the surrounding room air.
The pressure measurements at the impingement surface were
made for the nozzle-plate spacing’s of 0.25–4 for different
Reynolds numbers lying the range of 20,000 to 40,000. The
pressure distributions at the impingement surface were
obtained by moving the impingement plate with respect to the
jet, using a traversing unit with an accuracy of 0.1 mm. The
surface pressures were measured with a pressure tapping 0.5
mm placed at the center of the impingement plate. This
tapping was connected to a single column manometer to
determine the surface pressures. The Reynolds number
depends on the nozzle diameter, D, and the nozzle exit
velocity, U0. The pressure coefficient, Cp, is defined as
Cp=p/0.5V2
j where p represents the difference between the
local pressure on the impingement surface and the
atmospheric pressure while Vj represent the jet velocity
Fig.3. Layout of Experimental set-up
1) Air Blower.
2) Orifice flow-meter.
3) Differential manometer.
4) Flow control valve.
5) Nozzle.
6) Impingement plate assembly.
7) Traverse system
3. RESULTS&DISCUSSION
-4 -3 -2 -1 0 1 2 3 4
r/d
-1
0
1
2
3
4
Cp
Normal jet
z/d =0.25
Re = 21000
The radial distributions of the pressure coefficient
Fig -3(a) z/d=0.25, Re=21000
The fig illustrates the variation of Pressure coefficient with the
variation in r/d ratio. The fig clearly reveals that the pressure
coefficient is maximum at the stagnation point i.e. at r/d=0 and
it decreases with increase in r/d ratio. The Pressure coefficient
at the stagnation point is 1.845 and it becomes zero nearly at
r/d=0.7 the pressure coefficient was observed to become sub
atmospheric at r/d =0.72 and reach a minimum at r/d= 1.03,
and from then increases to ambient at r/d = 2.8. Pressure
recovery is inevitable since momentum must be conserved.
6
5 4 2
3
7
1
d
Stagnation
region
Target
surface
Nozzle
Free jet region
z
Boundary layer
Stagnation region
Wall-jet
region
3. IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
__________________________________________________________________________________________
Volume: 03 Special Issue: 03 | May-2014 | NCRIET-2014, Available @ http://www.ijret.org 593
-4 -3 -2 -1 0 1 2 3 4
r/d
-1
0
1
2
3
4
Cp
Normal jet
z/d =0.25
Re = 25000
Fig.-3 (b) .z/d=0.25, Re=25000
The above fig reveals that the pressure coefficient is maximum
at the stagnation point and it decreases with increase in r/d
ratio. The Pressure coefficient at the stagnation point is 1.929
and it becomes zero nearly at r/d=0.6 the pressure coefficient
was observed to become sub atmospheric at r/d =0.67 and
reach a minimum at r/d= 1.1, and from then increases to
ambient at r/d = 2.66. Pressure recovery is inevitable since
momentum must be conserved.
-4 -3 -2 -1 0 1 2 3 4
r/d
-1
0
1
2
3
4
Cp
Normal jet
z/d =0.25
Re = 35000
Fig.-3(c) z/d=0.25, Re=35000
The Pressure coefficient at the stagnation point is 1.948 and it
becomes zero nearly at r/d=0.6 the pressure coefficient was
observed to become sub atmospheric at r/d =0.66 and reach a
minimum at r/d= 1.03, and from then increases to ambient at
r/d = 2.72. Pressure recovery is inevitable since momentum
must be conserved.
-4 -3 -2 -1 0 1 2 3 4
r/d
0
0.4
0.8
1.2
1.6
Cp
Normal jet
z/d =0.5
Re = 28000
Fig-3 (a) z/d=0.5, Re=28000
The fig illustrates the variation of Pressure coefficient with the
variation in r/d ratio. The fig clearly reveals that the pressure
coefficient is maximum at the stagnation point i.e. at r/d=0 and
it decreases with increase in r/d ratio. The Pressure coefficient
at the stagnation point is 1.49 and it becomes zero nearly at
r/d=0.80, the pressure coefficient was observed to become sub
atmospheric at r/d =0.92 and reach a minimum at r/d= 2.25,
and from then increases to ambient at r/d = 3.2. Pressure
recovery is inevitable since momentum must be conserved
-4 -3 -2 -1 0 1 2 3 4
r/d
0
0.4
0.8
1.2
1.6
Cp
Normal jet
z/d =0.5
Re = 38000
Fig.-3 (b) z/d=0.5, Re=38000.
The above fig reveals that the pressure coefficient is maximum
at the stagnation point and it decreases with increase in r/d
ratio. The Pressure coefficient at the stagnation point is 1.45
and it becomes zero nearly at r/d=0.78 the pressure coefficient
was observed to become sub atmospheric at r/d =0.84 and
reach a minimum at r/d= 1.9, and from then increases to
ambient at r/d = 3.1. Pressure recovery is inevitable since
momentum must be conserved.
-4 -3 -2 -1 0 1 2 3 4
r/d
0
0.4
0.8
1.2
1.6
Cp
Normal jet
z/d =1
Re = 20000
Fig.-3 (a) z/d=1, Re=20000
The fig illustrates the variation of Pressure coefficient with the
variation in r/d ratio. The fig clearly reveals that the pressure
coefficient is maximum at the stagnation point i.e. at r/d=0 and
it decreases with increase in r/d ratio. The Pressure coefficient
at the stagnation point is 1.4 and it becomes zero nearly at
r/d=1.03, the pressure coefficient was observed to become sub
atmospheric at r/d =1.81, for further increase in r/d there is no
significant change in pressure coefficient.
-4 -3 -2 -1 0 1 2 3 4
r/d
0
0.4
0.8
1.2
1.6
Cp
Normal jet
z/d =1
Re = 30000
Fig.-3 (b) .z/d=1, Re=30000
4. IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
__________________________________________________________________________________________
Volume: 03 Special Issue: 03 | May-2014 | NCRIET-2014, Available @ http://www.ijret.org 594
The above fig reveals that the pressure coefficient is maximum
at the stagnation point and it decreases with increase in r/d
ratio. The Pressure coefficient at the stagnation point is 1.32
and it becomes zero nearly at r/d=1.15 the pressure coefficient
was observed to become sub atmospheric at r/d =1.21 and
reach a minimum at r/d= 2.45 for further increase in r/d there
is no significant change in pressure coefficient.
-4 -3 -2 -1 0 1 2 3 4
r/d
0
0.4
0.8
1.2
1.6
Cp
Normal jet
z/d =1
Re = 35000
Fig.-3 (c) z/d=1, Re=35000
The above fig reveals that the pressure coefficient is maximum
at the stagnation point and it decreases with increase in r/d
ratio. The Pressure coefficient at the stagnation point is 1.28
and it becomes zero nearly at r/d=1.09, the pressure coefficient
was observed to become sub atmospheric at r/d =1.33 and
reach a minimum at r/d= 1.9, for further increase in r/d there
is no significant change in pressure coefficient
-4 -3 -2 -1 0 1 2 3 4
r/d
0
0.4
0.8
1.2
1.6
Cp
Normal jet
z/d =1
Re = 37000
Fig-3(d) z/d=1, Re=37000
The above fig reveals that the pressure coefficient is maximum
at the stagnation point and it decreases with increase in r/d
ratio. The Pressure coefficient at the stagnation point is 1.309
and it becomes zero nearly at r/d=1.03, the pressure coefficient
was observed to become sub atmospheric at r/d =1.21 and
reach a minimum at r/d= 2.48, for further increase in r/d there
is no significant change in pressure coefficient
-4 -3 -2 -1 0 1 2 3 4
r/d
0
0.4
0.8
1.2
1.6
Cp
Normal jet
z/d =2
Re = 20000
Fig - 3(a) z/d=2, Re=20000
The fig illustrates the variation of Pressure coefficient with the
variation in r/d ratio. The fig clearly reveals that the pressure
coefficient is maximum at the stagnation point i.e. at r/d=0 and
it decreases with increase in r/d ratio. The Pressure coefficient
at the stagnation point is 1.14 and it becomes zero nearly at
r/d=1.09 the pressure coefficient was observed to become sub
atmospheric at r/d =0.72 and reach a minimum at r/d= 1.09,
and from then increases to ambient at r/d = 1.2. Pressure
recovery is inevitable since momentum must be conserved.
-4 -3 -2 -1 0 1 2 3 4
r/d
0
0.4
0.8
1.2
1.6
Cp
Normal jet
z/d =2
Re = 29000
Fig.-3 (b) z/d=2, Re=29000
The Pressure coefficient at the stagnation point is 1.26 and it
becomes zero nearly at r/d=1.3 the pressure coefficient was
observed to become sub atmospheric at r/d =0.67 and reach a
minimum at r/d= 1.3, and from then increases to ambient at
r/d = 1.5. Pressure recovery is inevitable since momentum
must be conserved.
-4 -3 -2 -1 0 1 2 3 4
r/d
0
0.4
0.8
1.2
1.6
Cp
Normal jet
z/d =2
Re = 34000
Fig.-3 (c) z/d=2, Re=34000
The Pressure coefficient at the stagnation point is 1.23 and it
becomes zero nearly at r/d=2.4 the pressure coefficient was
observed to become sub atmospheric at r/d =0.67 and reach a
minimum at r/d= 2.4, and from then increases to ambient at
5. IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
__________________________________________________________________________________________
Volume: 03 Special Issue: 03 | May-2014 | NCRIET-2014, Available @ http://www.ijret.org 595
r/d = 2.7. Pressure recovery is inevitable since momentum
must be conserved.
-4 -3 -2 -1 0 1 2 3 4
r/d
0
0.4
0.8
1.2
1.6
Cp
Normal jet
z/d=4
Re= 18000
Fig-3 (a) z/d=4, Re=18000
The fig illustrates the variation of Pressure coefficient with the
variation in r/d ratio. The fig clearly reveals that the pressure
coefficient is maximum at the stagnation point i.e. at r/d=0 and
it decreases with increase in r/d ratio. The Pressure coefficient
at the stagnation point is 1.17and it becomes zero nearly at
r/d=1.3, for further increase in r/d ratio there is no significant
changes in pressure coefficient.
-4 -3 -2 -1 0 1 2 3 4
r/d
0
0.4
0.8
1.2
1.6
Cp
Normal jet
z/d =4
Re = 28000
Fig.3 (b) z/d=4, Re=28000
The Pressure coefficient at the stagnation point is 1.15 and it
becomes zero nearly at r/d=1.21, for further increase in r/d
ratio there is no significant changes in pressure coefficient.
-4 -3 -2 -1 0 1 2 3 4
r/d
0
0.4
0.8
1.2
1.6
Cp
Normal jet
z/d =4
Re = 35000
Fig.-3(c) z/d=4, Re=35000
The Pressure coefficient at the stagnation point is 1.115 and it
becomes zero nearly at r/d=1.33, for further increase in r/d
ratio there is no significant changes in pressure coefficient.
-4 -3 -2 -1 0 1 2 3 4
r/d
0
0.4
0.8
1.2
1.6
Cp
Normal jet
z/d =4
Re = 38000
Fig.-3 (d) z/d=4, Re=38000.
The Pressure coefficient at the stagnation point is 1.10 and it
becomes zero nearly at r/d=1.59, for further increase in r/d
ratio there is no significant changes in pressure coefficient.
0 1 2 3 4
r/d
-1
0
1
2
3
4
Cp
Confined jet,z/d=0.25
Re=21000
Re=25000
Re=35000
Fig- 4 (a) .Effect of the r/d ratio on pressure distribution in
confined jet for z/d=0.25
The above fig illustrates the variation of Pressure coefficient
with the variation in r/d ratio for z/d=0.25. The fig clearly
reveals that the pressure coefficient is maximum at the
stagnation point i.e. at r/d=0 and it decreases with increase in
r/d ratio. From the fig it is clear that there is no significant
change in the pressure coefficient with variation in the
Reynolds number. The Pressure coefficient at the stagnation
point is 1.9 and it becomes zero nearly at r/d=0.65 the pressure
coefficient was observed to become sub atmospheric at r/d
=0.66and reach a minimum at r/d= 1.03, and from then
increases to ambient at r/d = 2.8. Pressure recovery is
inevitable since momentum must be conserved.
0 1 2 3 4
r/d
0
0.4
0.8
1.2
1.6
Cp
Confined jet, z/d=0.5
Re=18000
Re=28000
Re=38000
Normal jet
z/d =0.5
Re = 18000
Fig.-4 (b) .Effect of the r/d ratio on pressure distribution in
confined jet for z/d=0.5
6. IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
__________________________________________________________________________________________
Volume: 03 Special Issue: 03 | May-2014 | NCRIET-2014, Available @ http://www.ijret.org 596
The above fig illustrates the variation of Pressure coefficient
with the variation in r/d ratio for z/d=0.5. The fig clearly
reveals that the pressure coefficient is maximum at the
stagnation point i.e. at r/d=0 and it decreases with increase in
r/d ratio. From the fig it is clear that there is no significant
change in the pressure coefficient with variation in the
Reynolds number. The Pressure coefficient at the stagnation
point is 1.45 and it becomes zero nearly at r/d=0.65 the
pressure coefficient was observed to become sub atmospheric
at r/d=0.88 and reach a minimum at r/d= 1.98, and from then
increases to ambient at r/d = 3.1. Pressure recovery is
inevitable since momentum must be conserved.
0 1 2 3 4
r/d
0
0.4
0.8
1.2
1.6
Cp
Confined jet,z/d=1
Re=20000
Re=30000
Re=35000
Re=37000
Fig-4 (c) Effect of the r/d ratio on pressure distribution in
confined jet for z/d=1
The fig illustrates the variation of Pressure coefficient with the
variation in r/d ratio for z/d=1.0. The fig clearly reveals that
the pressure coefficient is maximum at the stagnation point i.e.
at r/d=0 and it decreases with increase in r/d ratio. From the
fig it is clear that there is no significant change in the pressure
coefficient with variation in the Reynolds number. The
Pressure coefficient at the stagnation point is 1.29 and it
becomes zero nearly at r/d=1.1 the pressure coefficient was
observed to become sub atmospheric at r/d =1.21 and reach a
minimum at r/d= 2.2, for further increase in r/d there is no
significant change in pressure coefficient.
0 1 2 3 4
r/d
0
0.4
0.8
1.2
1.6
Cp
Confined jet,z/d=2
Re=20000
Re=29000
Re=37000
Fig.-4 (d) .Effect of the r/d ratio on pressure distribution in
confined jet for z/d=2
The fig illustrates the variation of Pressure coefficient with the
variation in r/d ratio for z/d=1.0. The fig clearly reveals that
the pressure coefficient is maximum at the stagnation point i.e.
at r/d=0 and it decreases with increase in r/d ratio. From the
fig it is clear that there is no significant change in the pressure
coefficient with variation in the Reynolds number. The
Pressure coefficient at the stagnation point is 1.29 and it
becomes zero nearly at r/d=1.1 the pressure coefficient was
observed to become sub atmospheric at r/d =1.21 and reach a
minimum at r/d= 2.2, for further increase in r/d there is no
significant change in pressure coefficient.
0 1 2 3 4
r/d
0
0.4
0.8
1.2
1.6
Cp
confined jet,z/d=4
Re=18000
Re=28000
Re=35000
Re=38000
Fig.-4 (e) .Effect of the r/d ratio on pressure distribution in
confined jet for z/d=4
The fig illustrates the variation of Pressure coefficient with the
variation in r/d ratio for z/d=4. The fig clearly reveals that the
pressure coefficient is maximum at the stagnation point i.e. at
r/d=0 and it decreases with increase in r/d ratio. From the fig it
is clear that there is no significant change in the pressure
coefficient with variation in the Reynolds number. The
Pressure coefficient at the stagnation point is 1.13 and it
becomes zero nearly at r/d=1.33, for further increase in r/d
there is no significant change in pressure coefficient.
0 1 2 3 4
r/d
0
0.4
0.8
1.2
1.6
Cp
Normal jet,Re =50000
z/d=0.5
z/d=1
z/d=2
z/d=3
z/d=4
Fig.-4 (f) .Effect of the nozzle-to-plate spacing on pressure
distribution in unconfined jet a Re=50,000,
The fig illustrates the variation of Pressure coefficient with the
variation in r/d ratio for a Reynolds number of 50000. The fig
clearly reveals that the pressure coefficient is maximum for
z/d=0.5 at the stagnation point i.e. at r/d=0 and it decreases
with increase in r/d ratio. From the fig it is also clear that for
all other z/d ratios there is no significant change in the
pressure coefficient. The pressure coefficient becomes zero at
r/d=1.27, for further increase in r/d ratio there is no significant
change in pressure coefficient.
7. IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
__________________________________________________________________________________________
Volume: 03 Special Issue: 03 | May-2014 | NCRIET-2014, Available @ http://www.ijret.org 597
0 1 2 3 4
r/d
-1
0
1
2
Cp
confined jet Re=34000
z/d=0.25
z/d=0.5
z/d=1
z/d=2
z/d=4
Fig.-4 (g) .Effect of the nozzle-to-plate spacing on pressure
distribution in confined jet a Re=34,000,
The above figure clearly reveals that the pressure coefficient is
maximum at the stagnation point and decreases with increase
in r/d ratio. It is found that the pressure coefficient is
maximum i.e. 1.948 for z/d=0.25 at the stagnation point. The
pressure becomes sub atmospheric at approximately r/d=0.66
and then approaches to atmospheric value at r/d=2.72. For z/d
ratio of 0.5, the Pressure coefficient at the stagnation point is
1.28, the pressure coefficient was observed to become sub
atmospheric at r/d =1.33 and reach a minimum at r/d= 1.9, for
further increase in r/d there is no significant change in
pressure coefficient. For z/d ratios of 2 and 4 it is found that
pressure coefficient
4. CONCLUSIONS
Experimental investigations were carried out on the impinging
jet flow for Reynolds numbers up to 40,000 at various nozzle-
to-plate spacing’s for confined configuration. The
characteristics of an impinging circular jet region were found
to be sensitive to the nozzle-to-plate spacing. The sub
atmospheric regions which become stronger with increasing
Reynolds number and decreasing nozzle-to plate spacing
support the evidence of the recirculation zones. For
unconfined jet, no sub atmospheric region is observed on the
impingement surface for all the examined Reynolds numbers
and spacing’s.
The effect of the nozzle-to-plate spacing on the local surface
pressure distributions is studied for confined jets. It is seen
that, the pressure distributions are independent of the
Reynolds number and depend on nozzle-to-plate spacing only.
The maximum pressure occurs at the stagnation point (r/d=0)
for the all nozzle-to-plate spacing’s studied and as r/d
increases, the pressure decreases. At very low spacing
(z/d=0.25) stagnation pressure is rather larger than those of the
other spacing’s due to rapidly decreasing of axial velocity in
the deflection zone.
Figure a–e shows the pressure distributions of confined jet.
For the spacing’s up to z/d=1 and all the examined Reynolds
numbers, a sub atmospheric region occurs. As the nozzle-to-
plate spacing increases the fluid velocity decreases due to the
jet spreading, and thus the sub atmospheric region expands in
radial direction and its strength decreases.
Figure f shows the pressure distributions on impingement
surface in unconfined jet. For Reynolds number of 50000, at
very low spacing (z/d=0.5) stagnation pressure is rather larger
than those of the other spacing’s due to rapidly decreasing of
axial velocity in the deflection zone. In contrast to the
confined jet, no sub atmospheric region is observed for the
Reynolds number and the spacing’s studied. This situation can
be explained with the fluid velocity along the impingement
surface is lower with respect to the confined jet, due to no
flow confinement.
REFERENCES
[1]. Baydar E (1999) Confined impinging air jet at low
Reynolds Numbers. Exp. Thermal Fluid Sci 19:27–33
[2]. Baydar E, Ozmen Y (2005) an experimental and
numerical Investigation on a confined impinging air jet at high
Reynolds Numbers. Appl Thermal Eng 25:409–421
[3]. Ichimiya K, Yamada Y (2003) three dimensional heat
transfer of a confined circular impinging jet with buoyancy
effects.
[4]. ASME J Heat Transfer 125:250–256 Huber AM, Viskanta
R (1994) Convective heat transfer to a Confined impinging
array of air jets with spent air exits. ASME J Heat Transfer
116:570–576
[5]. Ashfort-Frost S, Jambunathan K, Whithney CF (1997)
Heat Transfer from a flat plate to a turbulent axisymmetric
impinging jet. Proc Inst Mech Eng 211:167–172
[6]. S. Ashfort-Frost, K. Jambunathan, Numerical prediction
of semicon jet impingement and comparison with
experimental data, Int. J. Numer. Methods Fluids 23 (1996)
295±306.
[7]. Yang Z, Sarkar P, Hu H (2011) an experimental study of
flow field around a high-rise building model in tornado-like
winds. J Fluids Struct 27(4):471–486
[8]. Zhang Y, Sarkar PP, Hu H (2012) Experimental and
numerical investigations on the flow characteristics of
microburst-like winds. 50th AIAA aerospace sciences meeting
including the new horizons forum and aerospace exposition
09–12 January 2012, Nashville, Tennessee, AIAA 20121197
[9]. Letchford CW, Chay MT (2002) Pressure distributions on
a cube in asimulated thunderstorm downburst, part B: moving
downburst observations. J Wind Eng Ind Aerodyn 90:733–753
[10]. Peterka JA, Hosoya N, Dodge S, Cochran L, Cermak JE
(1998) Area average peak pressures in a gable roof vortex
region. J Wind Eng Ind Aerodyn 77–78(1):205–215.