This document summarizes a study on the effect of a human-shaped obstacle on the velocity profiles of an air curtain. Computational fluid dynamics (CFD) was used to model air flow through an air curtain system with and without an obstacle. The presence of the obstacle disrupted the smooth, layered flow of the air curtain. Regions of low or no velocity were observed below the hands and legs of the obstacle, weakening the air curtain's effectiveness. While the obstacle improved velocities near the floor, it created areas where infiltration between indoor and outdoor air could occur more easily. The midsection area of the air curtain, where direct air enters the doorway, had the greatest influence on velocity profiles.
This document summarizes a study that used computational fluid dynamics (CFD) to analyze air flow velocity streamlines of air curtains. The study developed a prototype to simulate air curtain conditions at a doorway entrance. CFD simulations were conducted and validated against experimental results. The simulations analyzed velocity streamlines at different planes both with and without an obstacle (mannequin) present. Results showed straight downward air particle flow without an obstacle, but complex bending and mixing of streamlines around the obstacle. The study provides insight into air curtain barrier effectiveness under different conditions.
Computational Investigation on the Effect of Fences on Aerodynamic Characteri...ijtsrd
A computational study, to improve the stall characteristics of wing at high angles of attack, with and without fence configuration is done here. Wing fences, also known as boundary layer fences and potential fences are fixed aerodynamic devices attached to aircraft in the exactly middle of the span and two fences are fixed in the exactly middle of the wing span and two fences are fixed at 25 percentage of wing span from their corresponding wing tip. The main aim of this research is to improve the lift and stalling angle. A rectangular wing with different angles of attack is used. Modeling was done in CATIA V5 R20 and meshing and analyzing was taken in ANSYS workbench and CFX. Then the graph is drawn for CL and CD for various angles of attack and various models. Mohamed Hamdan. A "Computational Investigation on the Effect of Fences on Aerodynamic Characteristics of an Aircraft Wing" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-4 , June 2021, URL: https://www.ijtsrd.compapers/ijtsrd43687.pdf Paper URL: https://www.ijtsrd.comengineering/aeronautical-engineering/43687/computational-investigation-on-the-effect-of-fences-on-aerodynamic-characteristics-of-an-aircraft-wing/mohamed-hamdan-a
Iaetsd study and experimental analysis of linear and non linear behaviour ofIaetsd Iaetsd
The document describes an experimental study on the linear and non-linear behavior of pipe bends with ovality. Various pipe bend schedules including SCH 40 long radius, SCH 40 short radius, and SCH 80 short radius bends were tested under in-plane and out-of-plane bending moments both with and without internal pressure. Displacement and percentage change in ovality were measured in the intrados, crown, and extrados regions. The displacement in the intrados and extrados increased linearly with load. Allowable limit loads and ovality are suggested to avoid pipe rejection due to insufficient wall thickness. Mathematical and software results were compared to experimental results to optimize output.
Performance characteristics of a hybrid wing for uaveSAT Journals
Abstract Unmanned aerial vehicles (UAV) have become important in the surveillance sector of various governments. Their adavatage of high end technology and minimal risk of human life has been the major boost with respect to the research associated with UAVs. Over the years, the designing and optimization of the aerodynamics of these vehicles has gained lot of importance owing to the increasing urge to develop UAVs with better stability and endurance at subsonic speeds. Since the aircraft should have various performance characteristics as per the desired aerodyanamic requirements, it has been a challenging task to incorporate these characteristics through the use of a single homogeneous airfoil for the wing. With regard to the above discussion, this work deals with the comparison of performance characteristics of a hybrid wing consiting of two airfoil sections combined into a single wing and those of wings with each of the two homogeneous airfoil sections. The optimal wing dimensions for the surveilence UAV was obtained through MATLAB. Three separate models consiting of the hybrid wing, S1223 and E420 were developed through Solid Edge and imported into Fluent. Later, the wing models were subjected to aerodynamic analysis through the implementation of parameters experienced by the wing during the actual flight. The results obtained were compared in order to draw a conclusion regarding the advantages of using a hybrid wing as against the usage of wings with homogeneous airfoil. Keywords: UAV, Hybrid wing, Eppler 420, Seilig 1223 and Fluent.
Este documento proporciona información sobre los neurolépticos o antipsicóticos. Explica que se han desarrollado varias generaciones de neurolépticos típicos y atípicos. Los típicos ejercen su acción antipsicótica bloqueando los receptores dopaminérgicos D2, mientras que los atípicos causan menos efectos secundarios extrapiramidales. Además, clasifica los neurolépticos en 8 grupos según su estructura química, como las fenotiazinas, tioxantenos
This document summarizes a numerical analysis of turbulent kinetic energy, turbulent eddy dissipation, and pressure plots of air flow from an air curtain. A prototype air curtain system was modeled using computational fluid dynamics (CFD) to simulate experimental conditions. Turbulent kinetic energy, eddy dissipation, and pressure variation plots were generated at predefined planes and analyzed to understand the air flow behavior with and without an obstacle. The CFD results were validated against experimental data.
This document summarizes a computational fluid dynamics (CFD) analysis of natural cross ventilation in a generic isolated building. The study uses CFD simulations to analyze airflow patterns and pressure distributions with different opening configurations. Three cases are analyzed with varying inlet and outlet sizes and positions. The simulations solve the 3D steady Reynolds-averaged Navier-Stokes equations with a shear-stress transport turbulence model. Results show flow features like upstream vortices, indoor flow contraction and expansion, and rear recirculation zones. Pressure contours and velocity vectors are presented for each case.
Numerical analysis of velocity vectors plots and turbulent kinetic energyIAEME Publication
This document summarizes a numerical analysis of air flow through an air curtain mounted on a doorway frame using computational fluid dynamics (CFD). The study validated CFD results for velocity against experimental measurements, showing good agreement. CFD plots of velocity vectors, contours, and turbulent kinetic energy were analyzed. The air curtain flow was found to be continuous and straight downwards as desired, with higher turbulence near the ground where the flow is diverted sideways. Some cross flow between 0-0.83 m/s was found between the two inlet slits, indicating a weak point in the air barrier. It is recommended to minimize the separation between inlet slits to improve barrier effectiveness.
This document summarizes a study that used computational fluid dynamics (CFD) to analyze air flow velocity streamlines of air curtains. The study developed a prototype to simulate air curtain conditions at a doorway entrance. CFD simulations were conducted and validated against experimental results. The simulations analyzed velocity streamlines at different planes both with and without an obstacle (mannequin) present. Results showed straight downward air particle flow without an obstacle, but complex bending and mixing of streamlines around the obstacle. The study provides insight into air curtain barrier effectiveness under different conditions.
Computational Investigation on the Effect of Fences on Aerodynamic Characteri...ijtsrd
A computational study, to improve the stall characteristics of wing at high angles of attack, with and without fence configuration is done here. Wing fences, also known as boundary layer fences and potential fences are fixed aerodynamic devices attached to aircraft in the exactly middle of the span and two fences are fixed in the exactly middle of the wing span and two fences are fixed at 25 percentage of wing span from their corresponding wing tip. The main aim of this research is to improve the lift and stalling angle. A rectangular wing with different angles of attack is used. Modeling was done in CATIA V5 R20 and meshing and analyzing was taken in ANSYS workbench and CFX. Then the graph is drawn for CL and CD for various angles of attack and various models. Mohamed Hamdan. A "Computational Investigation on the Effect of Fences on Aerodynamic Characteristics of an Aircraft Wing" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-4 , June 2021, URL: https://www.ijtsrd.compapers/ijtsrd43687.pdf Paper URL: https://www.ijtsrd.comengineering/aeronautical-engineering/43687/computational-investigation-on-the-effect-of-fences-on-aerodynamic-characteristics-of-an-aircraft-wing/mohamed-hamdan-a
Iaetsd study and experimental analysis of linear and non linear behaviour ofIaetsd Iaetsd
The document describes an experimental study on the linear and non-linear behavior of pipe bends with ovality. Various pipe bend schedules including SCH 40 long radius, SCH 40 short radius, and SCH 80 short radius bends were tested under in-plane and out-of-plane bending moments both with and without internal pressure. Displacement and percentage change in ovality were measured in the intrados, crown, and extrados regions. The displacement in the intrados and extrados increased linearly with load. Allowable limit loads and ovality are suggested to avoid pipe rejection due to insufficient wall thickness. Mathematical and software results were compared to experimental results to optimize output.
Performance characteristics of a hybrid wing for uaveSAT Journals
Abstract Unmanned aerial vehicles (UAV) have become important in the surveillance sector of various governments. Their adavatage of high end technology and minimal risk of human life has been the major boost with respect to the research associated with UAVs. Over the years, the designing and optimization of the aerodynamics of these vehicles has gained lot of importance owing to the increasing urge to develop UAVs with better stability and endurance at subsonic speeds. Since the aircraft should have various performance characteristics as per the desired aerodyanamic requirements, it has been a challenging task to incorporate these characteristics through the use of a single homogeneous airfoil for the wing. With regard to the above discussion, this work deals with the comparison of performance characteristics of a hybrid wing consiting of two airfoil sections combined into a single wing and those of wings with each of the two homogeneous airfoil sections. The optimal wing dimensions for the surveilence UAV was obtained through MATLAB. Three separate models consiting of the hybrid wing, S1223 and E420 were developed through Solid Edge and imported into Fluent. Later, the wing models were subjected to aerodynamic analysis through the implementation of parameters experienced by the wing during the actual flight. The results obtained were compared in order to draw a conclusion regarding the advantages of using a hybrid wing as against the usage of wings with homogeneous airfoil. Keywords: UAV, Hybrid wing, Eppler 420, Seilig 1223 and Fluent.
Este documento proporciona información sobre los neurolépticos o antipsicóticos. Explica que se han desarrollado varias generaciones de neurolépticos típicos y atípicos. Los típicos ejercen su acción antipsicótica bloqueando los receptores dopaminérgicos D2, mientras que los atípicos causan menos efectos secundarios extrapiramidales. Además, clasifica los neurolépticos en 8 grupos según su estructura química, como las fenotiazinas, tioxantenos
This document summarizes a numerical analysis of turbulent kinetic energy, turbulent eddy dissipation, and pressure plots of air flow from an air curtain. A prototype air curtain system was modeled using computational fluid dynamics (CFD) to simulate experimental conditions. Turbulent kinetic energy, eddy dissipation, and pressure variation plots were generated at predefined planes and analyzed to understand the air flow behavior with and without an obstacle. The CFD results were validated against experimental data.
This document summarizes a computational fluid dynamics (CFD) analysis of natural cross ventilation in a generic isolated building. The study uses CFD simulations to analyze airflow patterns and pressure distributions with different opening configurations. Three cases are analyzed with varying inlet and outlet sizes and positions. The simulations solve the 3D steady Reynolds-averaged Navier-Stokes equations with a shear-stress transport turbulence model. Results show flow features like upstream vortices, indoor flow contraction and expansion, and rear recirculation zones. Pressure contours and velocity vectors are presented for each case.
Numerical analysis of velocity vectors plots and turbulent kinetic energyIAEME Publication
This document summarizes a numerical analysis of air flow through an air curtain mounted on a doorway frame using computational fluid dynamics (CFD). The study validated CFD results for velocity against experimental measurements, showing good agreement. CFD plots of velocity vectors, contours, and turbulent kinetic energy were analyzed. The air curtain flow was found to be continuous and straight downwards as desired, with higher turbulence near the ground where the flow is diverted sideways. Some cross flow between 0-0.83 m/s was found between the two inlet slits, indicating a weak point in the air barrier. It is recommended to minimize the separation between inlet slits to improve barrier effectiveness.
Numerical Simulation of a Centrifugal CompressorIJERA Editor
In this paper, the tip clearance effects on flow field of a low speed centrifugal compressor without and with partial shroud (PS) fitted on to the rotor blade tip at three values of tip clearance, viz. = 2.2%, 5.1% and 7.9% of rotor blade height at the exit at three flow coefficients, namely, = 0.18, 0.28, and 0.34, was studied. Based on the theory of computational fluid dynamics (CFD), performance curves and parameter distributions of the compressor were obtained from the 3-D numerical simulation by using ANSYS CFX 15.0. The centrifugal compressor in aerodynamic requirement is that edge velocities along the impeller channel passage surfaces like hub, shroud, pressure and suction surfaces vary smoothly without sudden decelerations, which cause flow separation leading to losses. Using the periodic boundaries and defined flow conditions at inflow / exit flow and blade rotations, the turbulent viscous flow between blade channels are computed. The efficiency related parameters using average quantities, besides flow pattern in terms of velocities, streamlines and pressure distribution on blade surfaces are graphically interpreted. An attempt is also made to study the influence of pressure loads on structural deformations in the chosen blade profile. This paper highlights aero-mechanical features of centrifugal impeller obtained from several numerical simulations, which are expected to provide a sound basis for further investigations. Keywords: Centrifugal compressor, Fl
Study of different contraction design of wind tunnel for better performance b...IRJET Journal
This document summarizes a study on improving the performance of a wind tunnel through computational fluid dynamics (CFD) modeling and analysis of different contraction designs. The study aims to improve flow uniformity and reduce flow separation in the contraction section of the wind tunnel. An existing wind tunnel is modeled using CFD and validated against experimental data. Different contraction geometries are then modeled and analyzed to determine an optimal design with improved flow characteristics. The CFD results show improvements in velocity uniformity and reductions in wall shear stresses with some contraction designs. Further experimental validation of the modified contraction designs is recommended.
IRJET- Design, Manufacturing and Testing of Open-Circuit Subsonic Wind Tunnel...IRJET Journal
This document provides a comprehensive review of the design, manufacturing, and testing of open-circuit subsonic wind tunnels. It discusses key components like the test section, contraction cone, diffuser, and drive system. For the settling chamber and honeycomb structure, the document recommends a length 5-10 times the diameter to reduce lateral turbulence, and notes hexagonal cells have the lowest pressure drop. It states the contraction ratio should be between 7-12 for optimum performance to eliminate axial flow fluctuations. The document also categorizes wind tunnels as open-circuit or closed-circuit, and describes classifications based on airflow speed like subsonic, transonic, supersonic, and hypersonic.
Design of vertical axis wind turbine for harnessing optimum powerIAEME Publication
The document discusses the design and testing of a vertical axis wind turbine with a sloped wind reducer to increase wind speed and optimize power generation. Experiments were conducted with wind reducers of various slopes in a wind tunnel. The results showed that a 300 sloped reducer increased wind speed by 1.5 times and power output by 3.38 times compared to no reducer. Based on these findings, the authors constructed a vertical axis wind turbine with a 10-foot tall, 10-foot long, 300 sloped glass reinforced plastic reducer.
Wind Load Analysis on High Rise Chimney using Computational Fluid DynamicsIRJET Journal
1) The document discusses a CFD analysis of wind load on high-rise industrial chimneys.
2) Different chimney designs and materials were modeled and simulated using ANSYS CFX software to determine critical high stress regions.
3) The results found that the mid-section of the chimney is the weakest part and experiences the highest stresses compared to the base and top. Chamfered edges were also found to significantly reduce induced pressures on the chimney.
This document summarizes a study on optimizing the aerodynamic design of wind turbine blades using winglets. The study used computational fluid dynamics (CFD) software to model and analyze a scaled wind turbine model with and without winglets. The results showed that adding winglets to the blades reduced drag and increased lift, leading to a 1.3% increase in power production. Pointing the winglets downstream further improved performance. In conclusion, winglets show potential for improving blade efficiency but their effects on increased thrust must also be considered.
Effect of spikes integrated to airfoil at supersonic speedeSAT Journals
Abstract
The objective of this is to analyse the flow field over an aerofoil section integrated with spikes at supersonic speed (Mach number
greater than 1). Use of spike integrated with aerofoil changes the flow characteristics over aerofoil and hence aerodynamic lift
and drag. The experiment consists of flow visualization graphs and measurement of coefficient of aerodynamic drag and lift.
Here we are using different shapes of spike like sharp edge and hemi spherical edge. In this we will compare the flow over
aerofoil with spike and without spike. The flow analysis is done by using Computational fluid dynamics (CFD). CFD is the study
of external flow over a body or internal flow through the body. CFD is aiding aero-dynamist to better understand the flow physics
and in turn to design efficient models. In short, CFD is playing a strong role as a design tool as well as a research tool.
Keywords: NACA 651-412 airfoil, spike, Ansys Fluent, Ansys ICEM CFD, Pressure Coefficient
This document discusses computational fluid dynamics (CFD) analysis of flow over an airfoil integrated with spikes at supersonic speeds. It presents the results of CFD simulations using ANSYS Fluent software to analyze the effect of adding either a sharp spike or hemispherical spike to a NACA 651-412 airfoil at Mach numbers over 1. The study found that the addition of spikes modifies the flow field over the airfoil and changes the aerodynamic lift and drag coefficients. Spikes help reduce problems like higher heating and separation that occur during supersonic flight.
This document discusses computational fluid dynamics (CFD) simulations of airflow distribution in rooms with different ceiling shapes. It investigates:
1) How ceiling shape (gable, gutter, gable-flat, gutter-flat roofs) and slope/arc angle affect airflow patterns in a 2D room model. Airflow is evaluated using velocity vectors, streamlines and contours.
2) The effect of adding passive controls like vertical obstacles on redirecting airflow and reducing vortex strength.
3) Comparisons of normalized horizontal velocity profiles for different ceiling shapes and slopes/arc angles at various planes, showing sensitivity to changes in ceiling design and placement of obstacles. The study aims to understand convective flow distribution
1.Critically assess the aerodynamic characteristics of a vehicle.
2.Select and specify the most appropriate methods for wind tunnel testing of scale models and interpret the results of the test.
3.Analyse and critically evaluate the aerodynamic cooling systems.
Analysis of wings using Airfoil NACA 4412 at different angle of attackIJMER
This document summarizes wind tunnel testing of the NACA 4412 airfoil at different angles of attack. The testing was conducted to analyze lift and drag forces on the airfoil at varying angles. The results found that lift increases with angle of attack until a maximum is reached, after which drag becomes dominant and stall occurs. Graphs and tables presented in the document compare experimental pressure and friction coefficient data from the wind tunnel tests to computational fluid dynamics simulations using different turbulence models. The models were able to accurately predict flow separation locations and other characteristics.
CFD INVESTIGATION OF CEILING SHAPE ON AIRFLOW DISTRIBUTION FOR A GENERIC 2-D ...IAEME Publication
Natural ventilation, which provides occupants with good indoor air quality and a high level of thermal comfort with reduced energy costs, has been drawing utmost importance in sustainable
strategy in building designs. Air flow distribution in a 2-D room with cross ventilation under different ceiling shape is investigated in this present paper using computational simulations carried with ANSYS-CFX, commercial CFD software.
Analysis of aerodynamic characteristics of a supercritical airfoil for low sp...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.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
CFD modelling calculation and simulation of busIRJET Journal
This document summarizes a CFD analysis of a bus interior to optimize passenger thermal comfort. The analysis uses CFD software to model the bus geometry and simulate air flow, temperature distribution, and passenger comfort under different operating conditions. Initial simulations were run with a coarse mesh to determine mesh size and turbulence parameters. Boundary conditions for the full simulation included an ambient temperature of 34°C, window heat flux of 250W/m2, and passenger temperature of 37°C. The full simulation results showed warmer temperatures and lower air velocities in the bus middle, indicating potential discomfort for those passengers. Modifications to the air ducts to increase middle airflow were recommended to improve thermal comfort.
This paper summarizes a computational fluid dynamics study of the aerodynamic performance of different front wing designs for a Formula SAE race car. The study used RANS simulations to analyze the downforce and drag produced by variations in the angle of attack and spacing of the wing elements. The results showed that a 5 degree angle of attack optimized the downforce to drag ratio. Increasing the spacing between wing elements also increased downforce by allowing momentum from one element to interact with the next element's boundary layer. Future work could involve parameterizing the wing geometry for shape optimization to further improve performance.
This academic article discusses numerical flow simulation of an elbow draft tube using STAR-CCM+ software. It summarizes the steps taken which include geometric modeling of the draft tube, mesh generation, specification of parameters like material properties and boundary conditions, and setting up the implicit unsteady simulation. Results of the simulation like pressure and velocity variations along the draft tube over different time steps are presented. Key findings are that pressure and velocity distributions are affected by time step size, with smaller time steps showing more uniform distributions. Performance metrics like head recovery and efficiency of the draft tube are computed and seen to decrease initially with time step before leveling off.
Cfd analysis in an ejector of gas turbine engine test bedIAEME Publication
This document summarizes a computational fluid dynamics (CFD) analysis of an ejector system used in a gas turbine engine test bed. The CFD analysis examined the ejector's performance with and without a debris guard. Without the guard, reducing the back pressure was found to achieve "double choking" at 0.1 bar, maximizing the entrainment ratio. With the guard, there was an 8.56% total pressure loss and 15% reduction in mass flow. The CFD analysis determined the impact of a debris guard and varying back pressure on the ejector's entrainment ratio and pressure losses.
IRJET-CFD Analysis of conceptual Aircraft bodyIRJET Journal
The document analyzes the aerodynamic performance of a conceptual aircraft model through computational fluid dynamics (CFD). CFD analysis is performed on the aircraft model at different angles of attack and taper ratios to determine lift and drag forces. The results show that lift force increases with angle of attack up to stall angle, while drag force also increases. Higher taper ratios are found to generate more lift force and less drag force compared to lower taper ratios. The CFD results provide valuable data to evaluate the aircraft design for applications in fighter jets, commercial aircraft, and drones.
CFD Analysis of conceptual Aircraft bodyIRJET Journal
The document analyzes the aerodynamic performance of a conceptual aircraft model through computational fluid dynamics (CFD). CFD analysis is performed on the aircraft model at different angles of attack and taper ratios to determine lift force, drag force, pressure distribution, and other parameters. The results show that lift force increases with angle of attack up to the stall point, while drag force also increases. Higher taper ratios are found to generate more lift force and less drag force compared to lower taper ratios. The CFD results provide valuable data to evaluate the design of the conceptual aircraft for applications such as fighter jets, commercial aircraft, and drones.
Tech transfer making it as a risk free approach in pharmaceutical and biotech iniaemedu
Tech transfer is a common methodology for transferring new products or an existing
commercial product to R&D or to another manufacturing site. Transferring product knowledge to the
manufacturing floor is crucial and it is an ongoing approach in the pharmaceutical and biotech
industry. Without adopting this process, no company can manufacture its niche products, let alone
market them. Technology transfer is a complicated, process because it is highly cross functional. Due
to its cross functional dependence, these projects face numerous risks and failure. If anidea cannot be
successfully brought out in the form of a product, there is no customer benefit, or satisfaction.
Moreover, high emphasis is in sustaining manufacturing with highest quality each and every time. It
is vital that tech transfer projects need to be executed flawlessly. To accomplish this goal, risk
management is crucial and project team needs to use the risk management approach seamlessly.
Integration of feature sets with machine learning techniquesiaemedu
This document summarizes a research paper that proposes a novel approach for spam filtering using selective feature sets combined with machine learning techniques. The paper presents an algorithm and system architecture that extracts feature sets from emails and uses machine learning to classify emails and generate rules to identify spam. Several metrics are identified to evaluate the efficiency of the feature sets, including false positive rate. An experiment is described that uses keyword lists as feature sets to train filters and compares the proposed approach to other spam filtering methods.
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In this paper, the tip clearance effects on flow field of a low speed centrifugal compressor without and with partial shroud (PS) fitted on to the rotor blade tip at three values of tip clearance, viz. = 2.2%, 5.1% and 7.9% of rotor blade height at the exit at three flow coefficients, namely, = 0.18, 0.28, and 0.34, was studied. Based on the theory of computational fluid dynamics (CFD), performance curves and parameter distributions of the compressor were obtained from the 3-D numerical simulation by using ANSYS CFX 15.0. The centrifugal compressor in aerodynamic requirement is that edge velocities along the impeller channel passage surfaces like hub, shroud, pressure and suction surfaces vary smoothly without sudden decelerations, which cause flow separation leading to losses. Using the periodic boundaries and defined flow conditions at inflow / exit flow and blade rotations, the turbulent viscous flow between blade channels are computed. The efficiency related parameters using average quantities, besides flow pattern in terms of velocities, streamlines and pressure distribution on blade surfaces are graphically interpreted. An attempt is also made to study the influence of pressure loads on structural deformations in the chosen blade profile. This paper highlights aero-mechanical features of centrifugal impeller obtained from several numerical simulations, which are expected to provide a sound basis for further investigations. Keywords: Centrifugal compressor, Fl
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This document provides a comprehensive review of the design, manufacturing, and testing of open-circuit subsonic wind tunnels. It discusses key components like the test section, contraction cone, diffuser, and drive system. For the settling chamber and honeycomb structure, the document recommends a length 5-10 times the diameter to reduce lateral turbulence, and notes hexagonal cells have the lowest pressure drop. It states the contraction ratio should be between 7-12 for optimum performance to eliminate axial flow fluctuations. The document also categorizes wind tunnels as open-circuit or closed-circuit, and describes classifications based on airflow speed like subsonic, transonic, supersonic, and hypersonic.
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The document discusses the design and testing of a vertical axis wind turbine with a sloped wind reducer to increase wind speed and optimize power generation. Experiments were conducted with wind reducers of various slopes in a wind tunnel. The results showed that a 300 sloped reducer increased wind speed by 1.5 times and power output by 3.38 times compared to no reducer. Based on these findings, the authors constructed a vertical axis wind turbine with a 10-foot tall, 10-foot long, 300 sloped glass reinforced plastic reducer.
Wind Load Analysis on High Rise Chimney using Computational Fluid DynamicsIRJET Journal
1) The document discusses a CFD analysis of wind load on high-rise industrial chimneys.
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3) The results found that the mid-section of the chimney is the weakest part and experiences the highest stresses compared to the base and top. Chamfered edges were also found to significantly reduce induced pressures on the chimney.
This document summarizes a study on optimizing the aerodynamic design of wind turbine blades using winglets. The study used computational fluid dynamics (CFD) software to model and analyze a scaled wind turbine model with and without winglets. The results showed that adding winglets to the blades reduced drag and increased lift, leading to a 1.3% increase in power production. Pointing the winglets downstream further improved performance. In conclusion, winglets show potential for improving blade efficiency but their effects on increased thrust must also be considered.
Effect of spikes integrated to airfoil at supersonic speedeSAT Journals
Abstract
The objective of this is to analyse the flow field over an aerofoil section integrated with spikes at supersonic speed (Mach number
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and drag. The experiment consists of flow visualization graphs and measurement of coefficient of aerodynamic drag and lift.
Here we are using different shapes of spike like sharp edge and hemi spherical edge. In this we will compare the flow over
aerofoil with spike and without spike. The flow analysis is done by using Computational fluid dynamics (CFD). CFD is the study
of external flow over a body or internal flow through the body. CFD is aiding aero-dynamist to better understand the flow physics
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This document discusses computational fluid dynamics (CFD) analysis of flow over an airfoil integrated with spikes at supersonic speeds. It presents the results of CFD simulations using ANSYS Fluent software to analyze the effect of adding either a sharp spike or hemispherical spike to a NACA 651-412 airfoil at Mach numbers over 1. The study found that the addition of spikes modifies the flow field over the airfoil and changes the aerodynamic lift and drag coefficients. Spikes help reduce problems like higher heating and separation that occur during supersonic flight.
This document discusses computational fluid dynamics (CFD) simulations of airflow distribution in rooms with different ceiling shapes. It investigates:
1) How ceiling shape (gable, gutter, gable-flat, gutter-flat roofs) and slope/arc angle affect airflow patterns in a 2D room model. Airflow is evaluated using velocity vectors, streamlines and contours.
2) The effect of adding passive controls like vertical obstacles on redirecting airflow and reducing vortex strength.
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1.Critically assess the aerodynamic characteristics of a vehicle.
2.Select and specify the most appropriate methods for wind tunnel testing of scale models and interpret the results of the test.
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Analysis of aerodynamic characteristics of a supercritical airfoil for low sp...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.
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
CFD modelling calculation and simulation of busIRJET Journal
This document summarizes a CFD analysis of a bus interior to optimize passenger thermal comfort. The analysis uses CFD software to model the bus geometry and simulate air flow, temperature distribution, and passenger comfort under different operating conditions. Initial simulations were run with a coarse mesh to determine mesh size and turbulence parameters. Boundary conditions for the full simulation included an ambient temperature of 34°C, window heat flux of 250W/m2, and passenger temperature of 37°C. The full simulation results showed warmer temperatures and lower air velocities in the bus middle, indicating potential discomfort for those passengers. Modifications to the air ducts to increase middle airflow were recommended to improve thermal comfort.
This paper summarizes a computational fluid dynamics study of the aerodynamic performance of different front wing designs for a Formula SAE race car. The study used RANS simulations to analyze the downforce and drag produced by variations in the angle of attack and spacing of the wing elements. The results showed that a 5 degree angle of attack optimized the downforce to drag ratio. Increasing the spacing between wing elements also increased downforce by allowing momentum from one element to interact with the next element's boundary layer. Future work could involve parameterizing the wing geometry for shape optimization to further improve performance.
This academic article discusses numerical flow simulation of an elbow draft tube using STAR-CCM+ software. It summarizes the steps taken which include geometric modeling of the draft tube, mesh generation, specification of parameters like material properties and boundary conditions, and setting up the implicit unsteady simulation. Results of the simulation like pressure and velocity variations along the draft tube over different time steps are presented. Key findings are that pressure and velocity distributions are affected by time step size, with smaller time steps showing more uniform distributions. Performance metrics like head recovery and efficiency of the draft tube are computed and seen to decrease initially with time step before leveling off.
Cfd analysis in an ejector of gas turbine engine test bedIAEME Publication
This document summarizes a computational fluid dynamics (CFD) analysis of an ejector system used in a gas turbine engine test bed. The CFD analysis examined the ejector's performance with and without a debris guard. Without the guard, reducing the back pressure was found to achieve "double choking" at 0.1 bar, maximizing the entrainment ratio. With the guard, there was an 8.56% total pressure loss and 15% reduction in mass flow. The CFD analysis determined the impact of a debris guard and varying back pressure on the ejector's entrainment ratio and pressure losses.
IRJET-CFD Analysis of conceptual Aircraft bodyIRJET Journal
The document analyzes the aerodynamic performance of a conceptual aircraft model through computational fluid dynamics (CFD). CFD analysis is performed on the aircraft model at different angles of attack and taper ratios to determine lift and drag forces. The results show that lift force increases with angle of attack up to stall angle, while drag force also increases. Higher taper ratios are found to generate more lift force and less drag force compared to lower taper ratios. The CFD results provide valuable data to evaluate the aircraft design for applications in fighter jets, commercial aircraft, and drones.
CFD Analysis of conceptual Aircraft bodyIRJET Journal
The document analyzes the aerodynamic performance of a conceptual aircraft model through computational fluid dynamics (CFD). CFD analysis is performed on the aircraft model at different angles of attack and taper ratios to determine lift force, drag force, pressure distribution, and other parameters. The results show that lift force increases with angle of attack up to the stall point, while drag force also increases. Higher taper ratios are found to generate more lift force and less drag force compared to lower taper ratios. The CFD results provide valuable data to evaluate the design of the conceptual aircraft for applications such as fighter jets, commercial aircraft, and drones.
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Tech transfer making it as a risk free approach in pharmaceutical and biotech iniaemedu
Tech transfer is a common methodology for transferring new products or an existing
commercial product to R&D or to another manufacturing site. Transferring product knowledge to the
manufacturing floor is crucial and it is an ongoing approach in the pharmaceutical and biotech
industry. Without adopting this process, no company can manufacture its niche products, let alone
market them. Technology transfer is a complicated, process because it is highly cross functional. Due
to its cross functional dependence, these projects face numerous risks and failure. If anidea cannot be
successfully brought out in the form of a product, there is no customer benefit, or satisfaction.
Moreover, high emphasis is in sustaining manufacturing with highest quality each and every time. It
is vital that tech transfer projects need to be executed flawlessly. To accomplish this goal, risk
management is crucial and project team needs to use the risk management approach seamlessly.
Integration of feature sets with machine learning techniquesiaemedu
This document summarizes a research paper that proposes a novel approach for spam filtering using selective feature sets combined with machine learning techniques. The paper presents an algorithm and system architecture that extracts feature sets from emails and uses machine learning to classify emails and generate rules to identify spam. Several metrics are identified to evaluate the efficiency of the feature sets, including false positive rate. An experiment is described that uses keyword lists as feature sets to train filters and compares the proposed approach to other spam filtering methods.
Effective broadcasting in mobile ad hoc networks using gridiaemedu
This document summarizes a research paper that proposes a new grid-based broadcasting mechanism for mobile ad hoc networks. The paper argues that flooding approaches to broadcasting are inefficient and cause network congestion. The proposed approach divides the network into a hierarchical grid structure. When a node needs to broadcast a message, it sends the message to the first node in the appropriate grid, which is then responsible for updating and forwarding the message within that grid. Simulation results showed the grid-based approach outperformed other broadcasting protocols and was more reliable, efficient and scalable.
Effect of scenario environment on the performance of mane ts routingiaemedu
The document analyzes the effect of scenario environment on the performance of the AODV routing protocol in mobile ad hoc networks (MANETs). It studies AODV performance under different scenarios varying network size, maximum node speed, and pause time. The performance is evaluated based on packet delivery ratio, throughput, and end-to-end delay. The results show that AODV performs best in some scenarios and worse in others, indicating that scenario parameters significantly impact routing protocol performance in MANETs.
Adaptive job scheduling with load balancing for workflow applicationiaemedu
This document discusses adaptive job scheduling with load balancing for workflow applications in a grid platform. It begins with an abstract that describes grid computing and how scheduling plays a key role in performance for grid workflow applications. Both static and dynamic scheduling strategies are discussed, but they require high scheduling costs and may not produce good schedules. The paper then proposes a novel semi-dynamic algorithm that allows the schedule to adapt to changes in the dynamic grid environment through both static and dynamic scheduling. Load balancing is incorporated to handle situations where jobs are delayed due to resource fluctuations or overloading of processors. The rest of the paper outlines the related works, proposed scheduling algorithm, system model, and evaluation of the approach.
This document summarizes research on transaction reordering techniques. It discusses transaction reordering approaches based on reducing resource conflicts and increasing resource sharing. Specifically, it covers:
1) A "steal-on-abort" technique that reorders an aborted transaction behind the transaction that caused the abort to avoid repeated conflicts.
2) A replication protocol that attempts to reorder transactions during certification to avoid aborts rather than restarting immediately.
3) Transaction reordering and grouping during continuous data loading to prevent deadlocks when loading data for materialized join views.
The document discusses semantic web services and their challenges. It provides an overview of semantic web technologies like WSDL, SOAP, UDDI, and OIL which are used to build semantic web services. The semantic web architecture adds semantics to web services through ontologies written in OWL and DAML+OIL. Key approaches to semantic web services include annotation, composition, and addressing privacy and security. However, semantic web services still face challenges in achieving their full potential due to issues in representation, reasoning, and a lack of real-world applications and data.
Website based patent information searching mechanismiaemedu
This document summarizes a research paper on developing a website-based patent information searching mechanism. It discusses how patent information can be used for technology development, rights acquisition and utilization, and management information. It describes different types of patent searches including novelty, validity, infringement, and state-of-the-art searches. It also evaluates and compares two major patent websites, Delphion and USPTO, in terms of their search capabilities and features.
Revisiting the experiment on detecting of replay and message modificationiaemedu
This document summarizes a research paper that proposes methods for detecting message modification and replay attacks in ad-hoc wireless networks. It begins with background on security issues in wireless networks and types of attacks. It then reviews existing intrusion detection systems and security techniques. Related work that detects attacks using features from the media access control layer or radio frequency fingerprinting is also discussed. The paper aims to present a simple, economical, and platform-independent system for detecting message modification, replay attacks, and unauthorized users in ad-hoc networks.
1) The document discusses the Cyclic Model Analysis (CMA) technique for sequential pattern mining which aims to predict customer purchasing behavior.
2) CMA calculates the Trend Distribution Function from sequential patterns to model purchasing trends over time. It then uses Generalized Periodicity Detection and Trend Modeling to identify periodic patterns and construct an approximating model.
3) The Cyclic Model Analysis algorithm is applied to further analyze the patterns, dividing the domain into segments where the distribution function is increasing or decreasing and applying the other techniques recursively to fully model the cyclic behavior.
Performance analysis of manet routing protocol in presenceiaemedu
This document analyzes the performance of different routing protocols in a mobile ad hoc network (MANET) under hybrid traffic conditions. It simulates a MANET with 50 nodes moving at speeds up to 20 m/s using the AODV, DSDV, and DSR routing protocols. Traffic included both constant bit rate and variable bit rate sources. Results found that AODV had lower average end-to-end delay and higher packet delivery ratios than DSDV and DSR as the percentage of variable bit rate traffic increased. AODV also performed comparably under both low and high node mobility scenarios with hybrid traffic.
Performance measurement of different requirements engineeringiaemedu
This document summarizes a research paper that compares the performance of different requirements engineering (RE) process models. It describes three RE process models - two existing linear models and the authors' iterative model. It also reviews literature on common RE activities and issues with descriptive models not reflecting real-world practices. The authors conducted interviews at two Indian companies to model their RE processes and compare them to the three models. They found the existing linear models did not fully capture the iterative nature of observed RE processes.
This document proposes a mobile safety system for automobiles that uses Android operating system. The system has two main components: a safety device and an automobile base unit. The safety device allows users to monitor the vehicle's location on a map, check its status, and control functions remotely. It communicates with the base unit in the vehicle using GPRS. The base unit collects data from sensors, determines the vehicle's GPS location, and can execute control commands like activating the brakes or switching off the engine. The document provides details on the design and algorithms of both components and includes examples of Java code implementation. The goal is to create an intelligent, secure and easy-to-use mobile safety system for vehicles using embedded systems and Android
Efficient text compression using special character replacementiaemedu
The document describes a proposed algorithm for efficient text compression using special character replacement and space removal. The algorithm replaces words with non-printable ASCII characters or combinations of characters to compress text files. It uses a dynamic dictionary to map words to their symbols. Spaces are removed from the compressed file in some cases to further reduce file size. Experimental results show the algorithm achieves better compression ratios than LZW, WinZip 10.0 and WinRAR 3.93 for various text file types while allowing lossless decompression.
The document discusses agile programming and proposes a new methodology. It provides an overview of existing agile methodologies like Scrum and Extreme Programming. Scrum uses short sprints to define tasks and deadlines. Extreme Programming focuses on practices like test-first development, pair programming, and continuous integration. The document notes drawbacks like an inability to support large or multi-site projects. It proposes designing a new methodology that combines the advantages of existing methods while overcoming their deficiencies.
Adaptive load balancing techniques in global scale grid environmentiaemedu
The document discusses various adaptive load balancing techniques for distributed applications in grid environments. It first describes adaptive mesh refinement algorithms that partition computational domains using space-filling curves or by distributing grids independently or at different levels. It also discusses dynamic load balancing using tiling and multi-criteria geometric partitioning. The document then covers repartitioning algorithms based on multilevel diffusion and the adaptive characteristics of structured adaptive mesh refinement applications. Finally, it discusses adaptive workload balancing on heterogeneous resources by benchmarking resource characteristics and estimating application parameters to find optimal load distribution.
A survey on the performance of job scheduling in workflow applicationiaemedu
This document summarizes a survey on job scheduling performance in workflow applications on grid platforms. It discusses an adaptive dual objective scheduling (ADOS) algorithm that takes both completion time and resource usage into account for measuring schedule performance. The study shows ADOS delivers good performance in completion time, resource usage, and robustness to changes in resource performance. It also describes the system architecture used, which includes a planner and executor component. The planner focuses on scheduling to minimize completion time while considering resource usage, and can reschedule if needed. The executor enacts the schedule on the grid resources.
A survey of mitigating routing misbehavior in mobile ad hoc networksiaemedu
This document summarizes existing methods to detect misbehavior in mobile ad hoc networks (MANETs). It discusses how routing protocols assume nodes will cooperate fully, but misbehavior like packet dropping can occur. It describes several techniques to detect misbehavior, including watchdog, ACK/SACK, TWOACK, S-TWOACK, and credit-based/reputation-based schemes. Credit-based schemes use virtual currencies to provide incentives for nodes to forward packets, while reputation-based schemes track nodes' past behaviors. The document aims to survey approaches for mitigating the impact of misbehaving nodes in MANET routing.
A novel approach for satellite imagery storage by classifyiaemedu
This document presents a novel approach for classifying and storing satellite imagery by detecting and storing only non-duplicate regions. It uses kernel principal component analysis to reduce the dimensionality and extract features of satellite images. Fuzzy N-means clustering is then used to segment the images into blocks. A duplication detection algorithm compares blocks to identify duplicate and non-duplicate regions. Only the non-duplicate regions are stored in the database, improving storage efficiency and updating speed compared to completely replacing existing images. Support vector machines are used to categorize the non-duplicate blocks into the appropriate classes in the existing images.
A self recovery approach using halftone images for medical imageryiaemedu
This document summarizes a proposed approach for securely transferring medical images over the internet using visual cryptography and halftone images. The approach uses error diffusion techniques to generate a halftone host image from the grayscale medical image. Shadow images are then created from the halftone host image using visual cryptography algorithms. When stacked together, the shadow images reveal the secret medical image. The halftone host image also contains an embedded logo that can be extracted to verify the integrity of the reconstructed image without a trusted third party.