Based on a mixture multiphase flow model,theRNG k–εturbulencemodelandfrozen rotor method were used to perform a numerical simulation of steady flow in the internal flow field of a sewage pump that transports solid and liquid phase flows. Resultsof the study indicate that the degree of wear on the front and the back of the blade suction surface from different densities of solid particles shows a completely opposite influencing trend. With the increase of delivered solid-phase density, the isobaric equilibrium position moves to the leading edge point of the blade, but the solid-phase isoconcentration point on the blade pressure surface and suction surface basically remains unchanged. The difference between hydraulic lift and water lift indelivering solid- and liquid-phase flows shows a rising trend with the increase of working flow
Evaluation of Air Flow Characteristics of Aerostatic Thrust Porous Bearings: A Numerical Approach by Marcelo Gustavo Coelho Resende, Leandro José da Silva, Cláudio de Castro Pellegrini and Túlio Hallak Panzera* in Evolutions in Mechanical Engineering: Crimson Publishers_ Structural engineering
Aerostatic porous bearings have been investigated in the last decades for precision engineering designs, since these bearings offer zero-friction and high operating speeds, as well as providing a very precise positioning system without external influence. Numerical methods such as CFD (Computational Fluid Dynamics) play an important role in the design and behavior analysis of porous aerostatic bearings, being possible to adjust the geometry and characteristics of the porous restrictor even before its manufacture In the present work, the behavior of the gas at the inlet and outlet of a porous thrust bearing made of cementitious composites is analysed by numerical simulation using CFD method. The results reveal a stable behavior of the cementitious porous bearing and a good correlation between numerical and experimental load capacities.
https://crimsonpublishers.com/eme/fulltext/EME.000520.php
For More open access journals in Crimson Publishers
please click on link: https://crimsonpublishers.com
For More Articles on Structural engineering
Please click on: https://crimsonpublishers.com/eme
Thin Film Pressure Estimation of Argon and Water using LAMMPSCSCJournals
In this work, we investigate the pressure and density characteristics of water film when simulated using the emerging technique called many body dissipative particle dynamics method. This work also layout the methodology of estimating local pressure from LAMMPS simulation using Harasima scheme. Using the triangular shaped cloud interpolation function, pressure and density are estimated at local bins and compared with the experimental database. Our results show good agreement for the molecular dynamics results of the argon system, while the many body dissipative particle model fails to simulate the water properties at room temperature. In its current form, the many body dissipative particle method cannot be used for accurate liquid vapor interfacial simulations and heat transfer studies.
The effect of rotational speed variation on the velocity vectors in the singl...IOSR Journals
The current investigation is aimed to simulate the three-dimensional complex internal flow in a
centrifugal pump impeller with five twisted blades by using a specialized computational fluid dynamics (CFD)
software ANSYS /FLUENT 14code with a standard k-ε two-equation turbulence model.
A single blade passage will be modeled to give more accurate results for velocity vectors on (blade, hub, and
shroud). The potential consequences of velocity vectors associated with operating a centrifugal compressor in
variable rotation speed.
A numerical three-dimensional, through flow calculations to predict velocity vectors through a
centrifugal pump were presented to examined the effect of rotational speed variation on the velocity vectors of
the centrifugal pump . The contours of the velocity vectors of the blade, hub, and shroud indicates low velocity
vectors in the suction side at high rotational speed (over operation limits )and the velocity vectors increases
gradually until reach maximum value at the leading edge (2.63×10 m/s) of the blade
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.
The sun is the source of solar energy and the solar energy is pollution free and available in ample amount which can be used for heating, electricity generation and coking purpose.The position of sun constantly varies so its intensity also varies which affect the heat quantity incident upon the system. The aim of present work is overcome this difficultly using wax type phase change material which behaves like heat storage medium as position of sun changes. This phase change material based solar water heater is fabricated and thermal performance evaluation can be carried out using K type thermocouple.
Evaluation of Air Flow Characteristics of Aerostatic Thrust Porous Bearings: A Numerical Approach by Marcelo Gustavo Coelho Resende, Leandro José da Silva, Cláudio de Castro Pellegrini and Túlio Hallak Panzera* in Evolutions in Mechanical Engineering: Crimson Publishers_ Structural engineering
Aerostatic porous bearings have been investigated in the last decades for precision engineering designs, since these bearings offer zero-friction and high operating speeds, as well as providing a very precise positioning system without external influence. Numerical methods such as CFD (Computational Fluid Dynamics) play an important role in the design and behavior analysis of porous aerostatic bearings, being possible to adjust the geometry and characteristics of the porous restrictor even before its manufacture In the present work, the behavior of the gas at the inlet and outlet of a porous thrust bearing made of cementitious composites is analysed by numerical simulation using CFD method. The results reveal a stable behavior of the cementitious porous bearing and a good correlation between numerical and experimental load capacities.
https://crimsonpublishers.com/eme/fulltext/EME.000520.php
For More open access journals in Crimson Publishers
please click on link: https://crimsonpublishers.com
For More Articles on Structural engineering
Please click on: https://crimsonpublishers.com/eme
Thin Film Pressure Estimation of Argon and Water using LAMMPSCSCJournals
In this work, we investigate the pressure and density characteristics of water film when simulated using the emerging technique called many body dissipative particle dynamics method. This work also layout the methodology of estimating local pressure from LAMMPS simulation using Harasima scheme. Using the triangular shaped cloud interpolation function, pressure and density are estimated at local bins and compared with the experimental database. Our results show good agreement for the molecular dynamics results of the argon system, while the many body dissipative particle model fails to simulate the water properties at room temperature. In its current form, the many body dissipative particle method cannot be used for accurate liquid vapor interfacial simulations and heat transfer studies.
The effect of rotational speed variation on the velocity vectors in the singl...IOSR Journals
The current investigation is aimed to simulate the three-dimensional complex internal flow in a
centrifugal pump impeller with five twisted blades by using a specialized computational fluid dynamics (CFD)
software ANSYS /FLUENT 14code with a standard k-ε two-equation turbulence model.
A single blade passage will be modeled to give more accurate results for velocity vectors on (blade, hub, and
shroud). The potential consequences of velocity vectors associated with operating a centrifugal compressor in
variable rotation speed.
A numerical three-dimensional, through flow calculations to predict velocity vectors through a
centrifugal pump were presented to examined the effect of rotational speed variation on the velocity vectors of
the centrifugal pump . The contours of the velocity vectors of the blade, hub, and shroud indicates low velocity
vectors in the suction side at high rotational speed (over operation limits )and the velocity vectors increases
gradually until reach maximum value at the leading edge (2.63×10 m/s) of the blade
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.
The sun is the source of solar energy and the solar energy is pollution free and available in ample amount which can be used for heating, electricity generation and coking purpose.The position of sun constantly varies so its intensity also varies which affect the heat quantity incident upon the system. The aim of present work is overcome this difficultly using wax type phase change material which behaves like heat storage medium as position of sun changes. This phase change material based solar water heater is fabricated and thermal performance evaluation can be carried out using K type thermocouple.
Study of Velocity and Pressure Distribution Characteristics Inside Of Catalyt...ijceronline
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
H-infinity controller with graphical LMI region profile for liquid slosh supp...TELKOMNIKA JOURNAL
This paper presents a H-infinity synthesis with pole clustering based on LMI region schemes for
liquid slosh control. Using LMI approach, the regional pole placement known as LMI region combined with
design objective in H-infinity controller guarantee a fast input tracking capability and very minimal liquid
slosh. A graphical profile of the transient response of liquid slosh suppression system with respect to pole
placement is very useful in giving more flexibility to the researcher in choosing a specific LMI region. With
the purpose to confirm the design of control scheme, a liquid slosh model is considered to represent
the lateral slosh movement. Supremacy of the proposed approach is shown by comparing the results with
hybrid model-free fuzzy-PID controller with derivative filter. The performance of the control schemes is
examined in terms of time response specifications of lateral tank tracking capability and level of liquid
slosh reduction.
Propeller cavitation is a major problem in ship operation and the costs of repair and maintenance is high for ship-owners. Proper design of propeller plays a very important role in life cycle and the performance of a vessel. The use of simulation to observe various parameters that affect cavitations can be helpful to optimize propeller performance. This project designs and simulates cavitations flow of a Kaplan series, Fixed Pitch Propeller (FPP) of a 48-metres Multipurpose Deck Ship at 11 knots. Simulation test was carried out for laminar and turbulent flow using Computational Fluid Dynamics (CFD) approach to observe cavitations occurrence at selected radius. The parameters considered are pitch angle, angle of attack, viscosity of sea water, operating vapour pressure in the sea water, engine power, lift and drag vectors of each of the blade sections, and resultant velocity of the fluid flow. Comparison of performance is made and it compares well with the theory. Thrust coefficient (KT), torque coefficient (KQ), thrust (T), advance coefficient (J), and cavitations number (σ), were calculated to deduce efficiency and validate the model. The study can be used to build a prototype physical model that could be beneficial for future additional experimentation investigation.
Key words: Simulation, cavitation, performance, propeller, CFD
International Journal of Mathematics and Statistics Invention (IJMSI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJMSI publishes research articles and reviews within the whole field Mathematics and Statistics, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
The effect of rotational speed variation on the static pressure in the centri...IOSR Journals
The current investigation is aimed to simulate the three-dimensional complex internal flow in a
centrifugal pump impeller with five twisted blades by using specialized computational fluid dynamics (CFD)
software ANSYS /FLUENT 14code with a standard k-ε two-equation turbulence model.
A single blade passage will be modeled to give more accurate results for static pressure contours on (blade,
hub, and shroud). The potential consequences of static pressure associated with operating a centrifugal
compressor in variable rotation speed.
A numerical three-dimensional, through flow calculations to predict static pressure through a
centrifugal pump were presented to examined the effect of rotational speed variation on the static pressure of
the centrifugal pump . The contours of the static pressure of the blade, hub, and shroud indicates negative low
static pressure in the suction side at high rotational speed (over operation limits )and the static pressure
increases gradually until reach maximum value at the leading edge (6×105 Pa) of the blade.
FLOW DISTRIBUTION NETWORK ANALYSIS FOR DISCHARGE SIDE OF CENTRIFUGAL PUMPijiert bestjournal
A computational fluid dynamics (CFD) analysis has been conducted to f ind the pressure losses for dividing and combining fluid flow through a junction of discharge system. Si mulations are performed for a range of flow ratios and equations are developed for pressure loss coeff icients at junctions. A mathematical model based on successive approximations then would be employed to estim ate the pressure losses. The proposed CFD based strategy can be used for the analysis of all the thr ee pipe branches of some diameter are selected along with equal length so that only the effect of bend angle can be studied. The effect of bend angle,pipe diameter,pipe length,Reynolds number on the resistance coeffi cient is studied. The software used is CATIA for modeling and ANSYS fluent for analysis purpose.
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
Study of Velocity and Pressure Distribution Characteristics Inside Of Catalyt...ijceronline
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
H-infinity controller with graphical LMI region profile for liquid slosh supp...TELKOMNIKA JOURNAL
This paper presents a H-infinity synthesis with pole clustering based on LMI region schemes for
liquid slosh control. Using LMI approach, the regional pole placement known as LMI region combined with
design objective in H-infinity controller guarantee a fast input tracking capability and very minimal liquid
slosh. A graphical profile of the transient response of liquid slosh suppression system with respect to pole
placement is very useful in giving more flexibility to the researcher in choosing a specific LMI region. With
the purpose to confirm the design of control scheme, a liquid slosh model is considered to represent
the lateral slosh movement. Supremacy of the proposed approach is shown by comparing the results with
hybrid model-free fuzzy-PID controller with derivative filter. The performance of the control schemes is
examined in terms of time response specifications of lateral tank tracking capability and level of liquid
slosh reduction.
Propeller cavitation is a major problem in ship operation and the costs of repair and maintenance is high for ship-owners. Proper design of propeller plays a very important role in life cycle and the performance of a vessel. The use of simulation to observe various parameters that affect cavitations can be helpful to optimize propeller performance. This project designs and simulates cavitations flow of a Kaplan series, Fixed Pitch Propeller (FPP) of a 48-metres Multipurpose Deck Ship at 11 knots. Simulation test was carried out for laminar and turbulent flow using Computational Fluid Dynamics (CFD) approach to observe cavitations occurrence at selected radius. The parameters considered are pitch angle, angle of attack, viscosity of sea water, operating vapour pressure in the sea water, engine power, lift and drag vectors of each of the blade sections, and resultant velocity of the fluid flow. Comparison of performance is made and it compares well with the theory. Thrust coefficient (KT), torque coefficient (KQ), thrust (T), advance coefficient (J), and cavitations number (σ), were calculated to deduce efficiency and validate the model. The study can be used to build a prototype physical model that could be beneficial for future additional experimentation investigation.
Key words: Simulation, cavitation, performance, propeller, CFD
International Journal of Mathematics and Statistics Invention (IJMSI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJMSI publishes research articles and reviews within the whole field Mathematics and Statistics, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
The effect of rotational speed variation on the static pressure in the centri...IOSR Journals
The current investigation is aimed to simulate the three-dimensional complex internal flow in a
centrifugal pump impeller with five twisted blades by using specialized computational fluid dynamics (CFD)
software ANSYS /FLUENT 14code with a standard k-ε two-equation turbulence model.
A single blade passage will be modeled to give more accurate results for static pressure contours on (blade,
hub, and shroud). The potential consequences of static pressure associated with operating a centrifugal
compressor in variable rotation speed.
A numerical three-dimensional, through flow calculations to predict static pressure through a
centrifugal pump were presented to examined the effect of rotational speed variation on the static pressure of
the centrifugal pump . The contours of the static pressure of the blade, hub, and shroud indicates negative low
static pressure in the suction side at high rotational speed (over operation limits )and the static pressure
increases gradually until reach maximum value at the leading edge (6×105 Pa) of the blade.
FLOW DISTRIBUTION NETWORK ANALYSIS FOR DISCHARGE SIDE OF CENTRIFUGAL PUMPijiert bestjournal
A computational fluid dynamics (CFD) analysis has been conducted to f ind the pressure losses for dividing and combining fluid flow through a junction of discharge system. Si mulations are performed for a range of flow ratios and equations are developed for pressure loss coeff icients at junctions. A mathematical model based on successive approximations then would be employed to estim ate the pressure losses. The proposed CFD based strategy can be used for the analysis of all the thr ee pipe branches of some diameter are selected along with equal length so that only the effect of bend angle can be studied. The effect of bend angle,pipe diameter,pipe length,Reynolds number on the resistance coeffi cient is studied. The software used is CATIA for modeling and ANSYS fluent for analysis purpose.
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
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
Optimization of Closure Law of Guide Vanes for an Operational Hydropower Plan...Dr. Amarjeet Singh
This paper addresses the optimization of twostage closure law of guide vanes in an operational
hydropower plant of Nepal. The mathematical model
has been established in commercial software Bentley
Hammer, whose correctness has been validated by
comparing the results with the data of experimental
load rejection test. The validated mathematical model
has been employed to find the parameters of optimum
closure pattern, which minimizes the non-linear
objective function of maximum water pressure and
maximum rotational speed of turbine.
Comparision of flow analysis through a different geometry of flowmeters using...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.
REVIEW OF FLOW DISTRIBUTION NETWORK ANALYSIS FOR DISCHARGE SIDE OF CENTRIFUGA...ijiert bestjournal
A computational fluid dynamics (CFD) analysis has been conducted to find the pressure losses for dividing and combining fluid flow through a junction of discharge system. Simulations are performed for a range of flow ratios and equations are developed for pressure loss coefficients at junctions. A mathematical model based on s uccessive approximations then would be employed to estimate the pressure losses. The proposed CFD based strategy can be used for the analysis of all the three pipe branches of s ome diameter are selected along with equal length so that only the effect of bend angle can be st udied. The effect of bend angle,pipe diameter,pipe length,reynolds number on the resistan ce coefficient is studied. The software used is CATIA for modeling and ANSYS fluent for analysis purpose.
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
The need for high pump performance and efficiency continue to encourage the study of flow between two parallel co-rotating discs in multiple discs pump or turbine. Therefore, this study entails the design, construction and CFD simulation of a 3D Tesla pump model axisymmetric swirling flow in order to enhance the understanding of Tesla pump for future development.
Method of solution entails designing and construction of a small prototype tesla pump and then using the design geometry and parameters to design and perform numerical simulation. The results of the numerical simulation were then analyzed.
The result obtained indicates static pressure to have minimum value of -4.7791Pa at the outlet and 13.777Pa at the pump inlet and with velocity magnitude having minimum velocity of 0.00m/s and maximum velocity of 4.12m/s. The strength of the velocity was seen to be very high at the pump outlet. The analysis radial velocity showed minimum value of -0.508m/s and maximum value of 3.981m/s with the radial velocity vector being concentrated at the discs periphery and outlet.
Model simulation results exhibited smooth pressure and velocity profiles. With the 3D simulation all flow variables are able to be predicted.
The need for high pump performance and efficiency continue to encourage the study of flow between two parallel co-rotating discs in multiple discs pump or turbine. Therefore, this study entails the design, construction and CFD simulation of a 3D Tesla pump model axisymmetric swirling flow in order to enhance the understanding of Tesla pump for future development.
Method of solution entails designing and construction of a small prototype tesla pump and then using the design geometry and parameters to design and perform numerical simulation. The results of the numerical simulation were then analyzed.
The result obtained indicates static pressure to have minimum value of -4.7791Pa at the outlet and 13.777Pa at the pump inlet and with velocity magnitude having minimum velocity of 0.00m/s and maximum velocity of 4.12m/s. The strength of the velocity was seen to be very high at the pump outlet. The analysis radial velocity showed minimum value of -0.508m/s and maximum value of 3.981m/s with the radial velocity vector being concentrated at the discs periphery and outlet.
Model simulation results exhibited smooth pressure and velocity profiles. With the 3D simulation all flow variables are able to be predicted.
Implementation of finite volume method in creeping flow around a circular cyl...eSAT Journals
Abstract
A Finite Volume Method have been performed in simulation of creeping flow around a circular cylinder contained between plates. By adopting the SIMPLE algorithm the governing equations are solved together with Papanastasious regularization. Apparent viscosity is calculated on each iteration by using forward difference operation. Yield surfaces are studied over the range of Oldroyd number 10≤Od≤〖10〗^4. The model results are found to be in good agreement with obtained results of the other method.
Keywords: Creeping flow, Finite Volume Method, Yielded and unyielded zone, Bingham number.
Implementation of finite volume method in creeping flow around a circular cyl...eSAT Journals
Abstract
A Finite Volume Method have been performed in simulation of creeping flow around a circular cylinder contained between plates. By adopting the SIMPLE algorithm the governing equations are solved together with Papanastasious regularization. Apparent viscosity is calculated on each iteration by using forward difference operation. Yield surfaces are studied over the range of Oldroyd number 10≤Od≤〖10〗^4. The model results are found to be in good agreement with obtained results of the other method.
Keywords: Creeping flow, Finite Volume Method, Yielded and unyielded zone, Bingham number.
Numerical Investigation of Turbulent Flow over a Rotating Circular Cylinder u...IJERA Editor
Recent advancements in the field of computational fluid mechanics and the availability of high performance with regard to rotating software computing cylinders (RCs) have drawn attention to the field of flow accelerated corrosion. (FAC). Current studies aim to numerically predict turbulent flow characteristics around the rotating cylinder and the concomitant effects on the wall shear stresses and local mass fraction of inhibitors that are directly related to corrosion rate. This 3-D numerical investigation was carried out using the commercial CFX package from which the where SST turbulence model was selected to compute the unknown Reynolds stresses term in the incompressible and viscid form of the Navier-Stokes equation. The effect of three different cylinder rotation speeds and three brine temperatures on the wall shear stress and on brine mixing is reported. Results of the simulations revealed that both cylinder rotation speed and the temperature of the brine significantly affect wall shear stress and mixing of the inhibitor that in turn affects corrosion rate
Similar to Numerical Calculation of Solid-Liquid two-Phase Flow Inside a Small Sewage Pump (20)
Hierarchical Digital Twin of a Naval Power SystemKerry Sado
A hierarchical digital twin of a Naval DC power system has been developed and experimentally verified. Similar to other state-of-the-art digital twins, this technology creates a digital replica of the physical system executed in real-time or faster, which can modify hardware controls. However, its advantage stems from distributing computational efforts by utilizing a hierarchical structure composed of lower-level digital twin blocks and a higher-level system digital twin. Each digital twin block is associated with a physical subsystem of the hardware and communicates with a singular system digital twin, which creates a system-level response. By extracting information from each level of the hierarchy, power system controls of the hardware were reconfigured autonomously. This hierarchical digital twin development offers several advantages over other digital twins, particularly in the field of naval power systems. The hierarchical structure allows for greater computational efficiency and scalability while the ability to autonomously reconfigure hardware controls offers increased flexibility and responsiveness. The hierarchical decomposition and models utilized were well aligned with the physical twin, as indicated by the maximum deviations between the developed digital twin hierarchy and the hardware.
About
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Technical Specifications
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
Key Features
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface
• Compatible with MAFI CCR system
• Copatiable with IDM8000 CCR
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
Application
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Student information management system project report ii.pdfKamal Acharya
Our project explains about the student management. This project mainly explains the various actions related to student details. This project shows some ease in adding, editing and deleting the student details. It also provides a less time consuming process for viewing, adding, editing and deleting the marks of the students.
Water scarcity is the lack of fresh water resources to meet the standard water demand. There are two type of water scarcity. One is physical. The other is economic water scarcity.
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdf
Numerical Calculation of Solid-Liquid two-Phase Flow Inside a Small Sewage Pump
1. The International Journal Of Engineering And Science (IJES)
|| Volume || 6 || Issue || 3 || Pages || PP 14-20 || 2017 ||
ISSN (e): 2319 – 1813 ISSN (p): 2319 – 1805
DOI: 10.9790/1813-0603021420 www.theijes.com Page 14
Numerical Calculation of Solid-Liquid two-Phase Flow Inside a
Small Sewage Pump
Yu-Liang Zhang 1
,Xiao-Jun Yang1
,Yan-Juan Zhao2
(1
College of Mechanical Engineering, Quzhou University, Quzhou 324000, China;
2
College of Information Engineering, Quzhou College of Technology, Quzhou 324000, China)
--------------------------------------------------------ABSTRACT-----------------------------------------------------------
Based on a mixture multiphase flow model,theRNG k–εturbulencemodelandfrozen rotor method were used to
perform a numerical simulation of steady flow in the internal flow field of a sewage pump that transports solid
and liquid phase flows. Resultsof the study indicate that the degree of wear on the front and the back of the
blade suction surface from different densities of solid particles shows a completely opposite influencing trend.
With the increase of delivered solid-phase density, the isobaric equilibrium position moves to the leading edge
point of the blade, but the solid-phase isoconcentration point on the blade pressure surface and suction surface
basically remains unchanged. The difference between hydraulic lift and water lift indelivering solid- and
liquid-phase flows shows a rising trend with the increase of working flow.
Keywords:sewage pump, numerical simulation, frozen rotor method, flow characteristics
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Date of Submission: 02 March 2017 Date of Accepted: 27 March 2017
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I. INTRODUCTION
Sewage pumpsconsist of both solid- and liquid-phase flow pumps and are key equipment for urban channel
cleanout[1~11]. Many scholars at home and abroad have carried out in-depth and meticulous research on
sewage pumps and have achieved productive results. However, with the wide application of the solid–liquid
pump, the shortcomings and deficiencies in the actual use were gradually exposed,such as low efficiency and
excessively wornwet parts. Meanwhile, due to the complexity of two-phase flow, the theoretical research and
design in this field is not mature. As the design of most existing products was based on the experiment, the
designed pump performance could not be guaranteed. Therefore, studying the internal flow of the pump to
provide a theoretical basis for realizingahigh-performingand stable-operating pump design is needed. The
presentstudyaims to conductanumerical simulation and analysis on solid-liquid two-phase flow pump to analyze
the impact of the density of solid-phase particles on sewage pump performance, including the hydraulic
performance of sewage pump and wear degree of wet parts. Through the analysis ofthe internal pressure and
dynamic deposition distribution of particles on the surface of the solid, the basic properties of sewage pump and
theoretical foundation for further design improvement could be predicted.
2 Physical model and solving method
II. PHYSICAL MODEL
The model was a medium specific speed centrifugal pump. Its basic performance parameters were as follows:
flow rate Q=50m3
/h, head H=20.54m, velocity n=2900r/min, shaft power Pa=3.54kW, efficiency
η=79.5%,andnet positive suction head NPSHC=2.59m. The main dimensions of the pumpwereas follows: inlet
diameter Dj=76mm, hub diameter dh=0mm, impeller outlet diameter D2=137mm, impeller outlet width
b2=14mm, blade outlet angle β2=30°.
2.2Computational domain
The appropriate extension of the straight-tube suction chamber was made to eliminate the influence of the given
inlet speed. Anappropriateextension of the pump outlet was also carried outto better calculate convergence. As
shown in Fig. 1,Tetrahedralmesheswere adopted in the impeller rotation region and volute static region, with
mesh numbers 435,530 and 597,127 respectively. Hexahedral mesheswere used in the suction chamber and
outlet extension, with mesh numbersof152,827 and 54,944 respectively. The total mesh number of the overall
computational domain was 1,240,428.
2. Numerical Calculation of Solid-Liquid two-Phase Flow Inside a Small Sewage Pump
DOI: 10.9790/1813-0603021420 www.theijes.com Page 15
Fig.1 Computational mesh
2.3 Solved equations
According totheBoussinesq approximation,
' ' 2
3
ji i
i j t t ij
j i i
uu u
u u k
x x x
(1)
Where t
refers to turbulent viscosity, which is the function coefficient of turbulent kinetic energy k and
turbulent dissipation rate ε.
Unsteady turbulent flow calculation used in the present study usedthe RNG k–ε two-equation model to close the
mean Reynolds stress. RNG k–ε turbulent model, which considers the rotation and swirling flow in the mean
flow, can better process the flow with high strain rate and great streamline curvature. The RNG k–ε
turbulentequations are as follows:
eff
d
2
d
i
k t ij
j j j
uk k
t x x x
S (2)
2
eff 1 2
d
2
d
i
t ij
j j j
u
C C R
t x x k x k
S (3)
where
1
2
ji
ij
j i
uu
x x
S ; eff t
;
2
t
k
C
ij
S refers to the strain rate tensor, andRrefers to
ε additional source terms in the equation, representing the effect of mean strain rate ε.Itisexpressed as follows:
3 2
0
3
(1 / )
, /
1
C
R S k
k
(4)
The model parameters in the above equations are Cμ=0.0845, C1ε=1.42, C2ε=1.68, αk=1.0, αε=0.769, β=0.012,
andη0=4.38.
2.4 Multiphase flow model
The general form of the ASMM is as follows, i.e., continuity equation,
,( ) ( ) 0m m m i
it x
u (5)
Whereρm is the density of the mixture, and um is the mass average velocity.
The momentum equation is
,,
, , ,
, , , ,
1
( ) ( )
m jm i
m m j m m i m j m
i j i j i
n
m j j k k D k i D k j
i k
uup
u u u
t x x x x x
g u u
x
F
(6)
3. Numerical Calculation of Solid-Liquid two-Phase Flow Inside a Small Sewage Pump
DOI: 10.9790/1813-0603021420 www.theijes.com Page 16
Wherepis the pressure, μm is the effective viscosity of the mixture, g is the gravitational acceleration, F is the
volume force, φ is the volume fraction, and uD,k is the drift velocity.
The volume fraction equation is
, , ,
( ) ( ) ( )s s s s m i s s D s i
i i
u u
t x x
(7)
1 1 1
( ) /
n n n
m k k m k k m k k k m
k k k
u u (8)
In this study, the calculated medium is a solid–liquid two-phase flow, where n = 2. If a steady flow calculation is
to be conducted, the phase of the local change rate will no longer exist in the above equation.
2.5 Solution settings
The dynamic and static coupling between rotor and stator in numerical calculation was achieved by means of the
frozen rotor method. Velocity inlet and free output were respectively used as the boundary conditions of the inlet
and outlet. Axial velocity of the pump inlet was calculated directly according to the given flow conditions and
pump inlet diameter. Turbulent kinetic energy and turbulent dissipation rate under the corresponding flow were
calculated based on axial velocity and pump inlet diameter. No-slip boundary condition was applied on all solid
walls considering viscosity, and standard wall function was used in near-wall low Reynolds number region to
deal with the problem from the high Reynolds number turbulence model. The coupling between velocity and
pressure was calculated by using SIMPLE algorithm. Solid particles were uniform spherical particles with
unchanged physical properties.
2.6Computational scheme
Under a designed flow rate (Q=50m3
/h) with10%solid-phase concentration and 0.10mmparticle diameter,
numerical calculation was conductedfora solid–liquid two-phase flow field under five conditions when the
particledensitieswere 500, 1000, 1500, 2000,and 2500kg/m3
. Numerical calculation of the solid–liquid
two-phase flow field was carried outunder different working conditions:10% solid-phase concentration,
0.10mmparticle diameter, and 2500kg/m3
particle density.
3Analysis of results
III. TOTAL PRESSURE DISTRIBUTION OF BLADE UNDER DIFFERENT
PARTICLE DENSITIES
Fig.2 shows the total pressure distribution on the blade pressure surface and blade suction surface in five
different delivering densities of solid particles. Regardless of whether on pressure surface or suction surface,
total pressure increased with the increase of the blade radius. In the case of the 500 kg/m3
density of delivering
solid particles, solid-phase density was smaller than the liquid-phase density. In most areas (relative length
ofabout 0.96), the total pressure on the blade pressure surface was higher than that on the suction surface. The
total pressure on the suction surface likewise started to be higher than that on the pressure surface. In other
words, position 0.96I was an isobaric equilibrium point of the pressure surface and the suction surface. For the
other four densities of delivering solid particles, the changing characteristic was similarlygeneral.The only
difference was that the isobaric equilibrium pointswere in different positions. In the four cases of densities of
delivering solid particles, i.e., 1000, 1500, 2000,and 2500kg/m3
, the relative positions of the isobaric
equilibrium pointswere 0.84, 0.75, 0.72, and 0.70, respectively. Generally speaking, with the increase of
delivering solid-phase density, the position of the isobaric equilibrium point was moving to the front edge point
of the blade.
(a) 500 (b)1000
4. Numerical Calculation of Solid-Liquid two-Phase Flow Inside a Small Sewage Pump
DOI: 10.9790/1813-0603021420 www.theijes.com Page 17
(c)1500 (d)2000
(e)2500
Fig.2 Distribution and variation of total pressure on the blade under different particle densities (kg/m3
)
3.2 Distribution of particle concentration of the blade under different particle densities
Fig.3 shows the distribution of solid-phase concentration on the blade pressure and suction surface under five
densities of delivering solid particles.When the densities of delivering solid-phase particles were different, the
difference in the concentration distributionswashighlysignificant. When the particle density (500 kg/m3
) was
smaller than the liquid-phase density (water) (1000 kg/m3
), the solid-phase concentration on the blade pressure
surface was higher than that on the blade suction surface in most areas ofthe blade surface. This finding
indicated that the blade pressure surface bore more serious wear. However, in the inlet of the blade, solid-phase
concentration on the blade pressure surface was lower than that on the suction surface. Therefore, the suction
surface bore more serious wear. Similarly, the position of the isoconcentration point (the point in the same
radius on the blade pressure surface and the suction surface with same solid-phase concentration) was
atapproximately0.11 (relative length). When particle density (1000 kg/m3
) was equal to liquid-phase density
(1000 kg/m3
), the solid-phase concentration on the blade pressure surface was equal to that on the suction
surface (10%) within the full range of the blade surface.This finding indicated that the blade pressure surface
and suction surface bore equal wear. When particle density (1500, 2000, and 2500 kg/m3
) were greater than
liquid-phase density (1000 kg/m3
),solid-phase concentration on the blade suction surface was significantly
higher than that on the pressure surface in most areas on the blade surface. This result indicated that the blade
suction surface bore more serious wear. However, under the latter three conditions, the position of solid-phase
isoconcentrationpointswasin 0.11, 0.13, and 0.13 (relative length). Specifically, the position of solid-phase
isoconcentration point on the blade pressure and suction surface was almost unchanged with the increase of the
density of delivering solid particles. This finding indicated that the degree of wear of the blade pressure surface
and the suction surface did not change due to the change in particle density.
5. Numerical Calculation of Solid-Liquid two-Phase Flow Inside a Small Sewage Pump
DOI: 10.9790/1813-0603021420 www.theijes.com Page 18
(a) 500 (b)1000
(b) 1500 (d)2000
(e)2500
Fig.3 Distribution of particle concentrations on the blade under different particle densities (kg/m3
)
3.3 Total pressure and streamline
Fig.4 shows total pressure and streamline obtained from the calculation under different densitiesof delivering
solid-phase particles. Under different densitiesof delivering solid-phase particles, streamlines in all flow
channels in the impeller were not greatly different and weregenerallyvery similar. The reason was that the
density of delivering solid-phase particles was different, but the calculated working condition was the designed
working condition, and the corresponding internal flow conditions at that time were generally good without a
significantarea of stalled phenomenon.
6. Numerical Calculation of Solid-Liquid two-Phase Flow Inside a Small Sewage Pump
DOI: 10.9790/1813-0603021420 www.theijes.com Page 19
(a)500 (b)1000 (c)1500 (d)2000 (e)2500
Fig.4Distribution of total pressure and streamline under different particle densities (kg/m3
)
3.4Difference in the external characteristics of solid–liquid two-phase flow
Under the designed working condition (Q=50m3
/h) and in the cases wherethe diameter of solid particle is
0.10mm, solid-phase delivering concentration is 10%, and the density of solid particles is 2500kg/m3
, the flow
calculation of water and solid-liquid two-phase flow was carried out. The calculation result of the external
characteristics of both is shown inFig.5. The calculation is carried out within the working condition of 0.60–1.40
times that of rated flow. Under three working conditions that deliver flow at30, 50, and 70m3
/h, respectively, the
calculation heads as delivering water medium are 22.03, 20.68, and 16.90m. When the calculation heads as
delivering solid-liquid two-phase flow are 16.15, 13.81,and 7.61m, respectively, the differences under the
corresponding flow between both of them are 5.88, 6.87,and 9.29m, respectively. Whether delivering a
single-phase flow or a solid-liquid two-phase flow, hydraulic head was down with the increase of delivering
flow. The hydraulic head delivering solid-liquid two-phase flow was obviously lower than that delivering water
medium, and the difference between both increased with the increase of the flow rate.
Fig.5 Comparison of external characteristics between delivering water and solid-liquid two-phase flow
3.5 Solid-phase concentration distribution
Under the same condition, solid-phase concentration distribution on the pump surface as the model pump was
delivering solid-liquid two-phase flow under three working conditions (flow rates were 35, 50, and 65m3
/h) is
shown in Fig.6. The solid-liquid concentration distributions under three conditions were similar. This finding
indicated that the degree of wear on theinternal surface of the volute, the front cover, and the back cover were
similar.
7. Numerical Calculation of Solid-Liquid two-Phase Flow Inside a Small Sewage Pump
DOI: 10.9790/1813-0603021420 www.theijes.com Page 20
(a)0.7 (b)1.0 (c)1.3
Fig.6Solid-phase concentration distributions on pump surface(Q/Qd)
4 Conclusions
(1) With the increase of delivering solid-phase density, the position of isobaric equilibrium point was moving
to the front edge of the blade, but the position of solid-phase isoconcentration point on the blade pressure
surface and suction surface was basically unchanged. This result indicated that the wear and tear on the
blade pressure surface and suction surface was not changed with the change of particle density.
(2) Hydraulic head as delivering solid-liquid two-phase flow was significantly lower than water head, and the
difference between them increased with the increase of flow rate.
ACKNOWLEDGEMENT
The work was supported by the Zhejiang Provincial Science and Technology Project (No.2015C31129,
No.2016C31127), Academic Foundation of Quzhou University (No.XNZQN201508).
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