This document summarizes a study that uses computational fluid dynamics (CFD) to simulate the internal flow in a centrifugal pump with varying rotational speeds. The study models a single blade passage of a five-bladed centrifugal pump impeller to accurately predict velocity vectors on the blade, hub, and shroud. Results show that at higher rotational speeds above the design point, velocity vectors increase more gradually until reaching a maximum value at the leading edge of the blade. The analysis concludes that velocity vectors in the suction side remain approximately constant, but increase to a higher maximum at the leading edge as rotational speed increases, especially above the design point.
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.
This paper describes the operating principle and the constructive solution for a rotating volumetric pump with two profiled rotors. Calculation relations are established for the flow rate and the driving power of the rotating pump. An example of a calculation for determining the pump driving power according to the conveyed flow rate is presented; the flow rates were chosen for the case when the pump would be used in an irrigation pumping station. The pump can carry different categories of fluids such as: (1) Fluids with suspended particles (water + ash, water + sand), (2) Viscous fluids (oil, diesel, oil), (3) Multi-phase fluids (water + air, water + steam).
Numerical Calculation of Solid-Liquid two-Phase Flow Inside a Small Sewage Pumptheijes
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
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.
This paper describes the operating principle and the constructive solution for a rotating volumetric pump with two profiled rotors. Calculation relations are established for the flow rate and the driving power of the rotating pump. An example of a calculation for determining the pump driving power according to the conveyed flow rate is presented; the flow rates were chosen for the case when the pump would be used in an irrigation pumping station. The pump can carry different categories of fluids such as: (1) Fluids with suspended particles (water + ash, water + sand), (2) Viscous fluids (oil, diesel, oil), (3) Multi-phase fluids (water + air, water + steam).
Numerical Calculation of Solid-Liquid two-Phase Flow Inside a Small Sewage Pumptheijes
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
Three-dimensional Streamline Design of the Pump Flow Passage of Hydrodynamic...IJMER
The design methods of three-element, centripetal turbine hydrodynamic torque converters
were investigated. A new design method, three-dimensional streamline design method, was proposed.
Firstly, the three-dimensional central streamline of the flow passage was designed and the streamline
consists of a circular arc and a short straight line segment. After that, the central streamline equation was
obtained and the design path equation was derived. Next, any other meridional flow path can numerically be
obtained. Finally, the three-dimensional streamline corresponding to any meridional flow path was
computed numerically. Investigation results show that the proposed method is feasible and possesses
obvious advantages. First, the curvature radius of the three-dimensional central streamline remains
unchanged, while any other three-dimensional streamline is close to a circular arc as well. Therefore, the
energy losses caused by streamline bending can be reduced. Second, because the fluid particle near the flow
passage outlet flows in a straight line law and the energy losses due to flow deviation can be reduced. Third,
all the three-dimensional streamlines are theoretically located in an identical plane. Thereby energy losses
caused by the turbulence can be reduced. Fourth, because of the flat blades, the manufacture cost of a torque
converter can be reduced.
Optimization of design of mixed flow centrifugal pump impeller using cfdeSAT Journals
Abstract
Centrifugal pumps are widely used hydraulic machines, irrespective of the fact that their performance is generally not very good. So, turning them into more efficient machines is quite a challenge. The performance of a centrifugal pump is highly dependent on its geometrical parameters and its vane profile. In order to analyze the flow through complex systems like centrifugal pumps, Computation fluid dynamics (CFD) has been used. This work aims to study the performance analysis of a centrifugal mixed flow pump designed to deliver 0.25 m3/s of water with a head of 20 m at a speed of 1450 rpm using ANSYS CFX (ver.14.0). PTC Creo (ver. 2.0) has been used to model the pump unit. The performance of the pump was first determined using the existing vane angles and thickness of the blade then, the inlet vane angle, the outlet vane angle along with the thickness of the blade has been varied to analyze the pump’s performance . The results show that for an initial inlet angle 21.08˚, outlet angle 16.28˚ and blade thickness as 10mm, the efficiency of the pump was 84%. However, the efficiency of pump rises to 89.19% for the optimized angles and blade thickness.
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
International Journal of Engineering Research and Development (IJERD)IJERD Editor
journal publishing, how to publish research paper, Call For research paper, international journal, publishing a paper, IJERD, journal of science and technology, how to get a research paper published, publishing a paper, publishing of journal, publishing of research paper, reserach and review articles, IJERD Journal, How to publish your research paper, publish research paper, open access engineering journal, Engineering journal, Mathemetics journal, Physics journal, Chemistry journal, Computer Engineering, Computer Science journal, how to submit your paper, peer reviw journal, indexed journal, reserach and review articles, engineering journal, www.ijerd.com, research journals,
yahoo journals, bing journals, International Journal of Engineering Research and Development, google journals, hard copy of journal
Head Loss Estimation for Water Jets from Flip Bucketstheijes
Water jet issued from flip bucket at the end of the spillway of a dam can be a threat for the stability and safety of the dam body due to subsequent scour at the impingement point. However, a strong jet from the flip bucket interacts with the surrounding air and develops into an aerated turbulent jet while the jet impact and scouring effect is reduced significantly. Aeration of the jet, at the same time, cause head losses along the trajectory. An experimental study is conducted to measure the trajectory lengths and investigate the effect of water depth in the river on the dynamic pressures acted on the river bed. The trajectory lengths with and without air entrainment are calculated using empirical equations and compared with the measurements. Head losses due to air entrainment are determined using the difference of the trajectory lengths with and without aeration, based on the projectile motion theory. Numerical simulation of the flow over the spillway, along the flip bucket and the jet trajectory is made and the results are compared with the experimental data. It is observed that trajectory lengths obtained from experiments, numerical simulation and empirical formulas are comparable with negligible differences. This allows us to combine alternate approaches to determine the trajectory lengths with and without air entrainment and estimate the head losses accordingly.
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
Atmospheric turbulent layer simulation for cfd unsteady inlet conditionsStephane Meteodyn
The aim of this work is to bridge the gap between experimental approaches in wind tunnel testing and numerical computations, in the field of structural design against strong winds. This paper focuses on the generation of an unsteady flow field, representative of a natural wind field, but still compatible with CFD inlet requirements. A simple and “naïve” procedure is explained, and the results are successfully compared to some standards.
Static analysis of c s short cylindrical shell under internal liquid pressure...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
Static analysis of c s short cylindrical shell under internal liquid pressure...eSAT Journals
Abstract The static analysis of C-S short cylindrical shell under internal liquid pressure is presented. Pasternak’s equation was adopted as the governing differential equation for cylindrical shell. By satisfying the boundary conditions of the C-S short cylindrical shell in the general polynomial series shape function, a particular shape function for the shell was obtained. This shape function was substituted into the total potential energy functional of the Ritz method, and by minimizing the functional, the unknown coefficient of the particular polynomial shape function was obtained. Bending moments, shear forces and deflections of the shell were determined, and used in plotting graphs for cases with a range of aspect ratios, 1 ≤ L/r ≤ 4. For case 1, the maximum deflection was 8.65*10-4metres, maximum rotation was 3.06*10- 3radians, maximum bending moment was -886.45KNm and maximum shear force was -5316.869KN. For case 2, the maximum deflection was 2.18*10-4metres, maximum rotation was 7.74*10-4radians, maximum bending moment was -223.813KNm and maximum shear force was -1342.878KN. For case 3, the maximum deflection was 9.71*10-5metres, maximum rotation was 3.44*10-4radians, maximum bending moment was -99.463KNm and maximum shear force was -596.779KN. For case 4,the maximum deflection was 5.48*10-5metres, maximum rotation was 1.94*10- 4radians, maximum bending moment was -56.097KNm and maximum shear force was -336.584KN. It was observed that as the aspect ratio increases from 1 to 4, the deflections, bending moments and shear forces decreases, and the shell tends to behave like long cylindrical shell. Keywords: Static analysis, Short Cylindrical Shell, internal liquid pressure, Polynomial series shape function, Boundary condition, Ritz method.
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.
Three-dimensional Streamline Design of the Pump Flow Passage of Hydrodynamic...IJMER
The design methods of three-element, centripetal turbine hydrodynamic torque converters
were investigated. A new design method, three-dimensional streamline design method, was proposed.
Firstly, the three-dimensional central streamline of the flow passage was designed and the streamline
consists of a circular arc and a short straight line segment. After that, the central streamline equation was
obtained and the design path equation was derived. Next, any other meridional flow path can numerically be
obtained. Finally, the three-dimensional streamline corresponding to any meridional flow path was
computed numerically. Investigation results show that the proposed method is feasible and possesses
obvious advantages. First, the curvature radius of the three-dimensional central streamline remains
unchanged, while any other three-dimensional streamline is close to a circular arc as well. Therefore, the
energy losses caused by streamline bending can be reduced. Second, because the fluid particle near the flow
passage outlet flows in a straight line law and the energy losses due to flow deviation can be reduced. Third,
all the three-dimensional streamlines are theoretically located in an identical plane. Thereby energy losses
caused by the turbulence can be reduced. Fourth, because of the flat blades, the manufacture cost of a torque
converter can be reduced.
Optimization of design of mixed flow centrifugal pump impeller using cfdeSAT Journals
Abstract
Centrifugal pumps are widely used hydraulic machines, irrespective of the fact that their performance is generally not very good. So, turning them into more efficient machines is quite a challenge. The performance of a centrifugal pump is highly dependent on its geometrical parameters and its vane profile. In order to analyze the flow through complex systems like centrifugal pumps, Computation fluid dynamics (CFD) has been used. This work aims to study the performance analysis of a centrifugal mixed flow pump designed to deliver 0.25 m3/s of water with a head of 20 m at a speed of 1450 rpm using ANSYS CFX (ver.14.0). PTC Creo (ver. 2.0) has been used to model the pump unit. The performance of the pump was first determined using the existing vane angles and thickness of the blade then, the inlet vane angle, the outlet vane angle along with the thickness of the blade has been varied to analyze the pump’s performance . The results show that for an initial inlet angle 21.08˚, outlet angle 16.28˚ and blade thickness as 10mm, the efficiency of the pump was 84%. However, the efficiency of pump rises to 89.19% for the optimized angles and blade thickness.
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
International Journal of Engineering Research and Development (IJERD)IJERD Editor
journal publishing, how to publish research paper, Call For research paper, international journal, publishing a paper, IJERD, journal of science and technology, how to get a research paper published, publishing a paper, publishing of journal, publishing of research paper, reserach and review articles, IJERD Journal, How to publish your research paper, publish research paper, open access engineering journal, Engineering journal, Mathemetics journal, Physics journal, Chemistry journal, Computer Engineering, Computer Science journal, how to submit your paper, peer reviw journal, indexed journal, reserach and review articles, engineering journal, www.ijerd.com, research journals,
yahoo journals, bing journals, International Journal of Engineering Research and Development, google journals, hard copy of journal
Head Loss Estimation for Water Jets from Flip Bucketstheijes
Water jet issued from flip bucket at the end of the spillway of a dam can be a threat for the stability and safety of the dam body due to subsequent scour at the impingement point. However, a strong jet from the flip bucket interacts with the surrounding air and develops into an aerated turbulent jet while the jet impact and scouring effect is reduced significantly. Aeration of the jet, at the same time, cause head losses along the trajectory. An experimental study is conducted to measure the trajectory lengths and investigate the effect of water depth in the river on the dynamic pressures acted on the river bed. The trajectory lengths with and without air entrainment are calculated using empirical equations and compared with the measurements. Head losses due to air entrainment are determined using the difference of the trajectory lengths with and without aeration, based on the projectile motion theory. Numerical simulation of the flow over the spillway, along the flip bucket and the jet trajectory is made and the results are compared with the experimental data. It is observed that trajectory lengths obtained from experiments, numerical simulation and empirical formulas are comparable with negligible differences. This allows us to combine alternate approaches to determine the trajectory lengths with and without air entrainment and estimate the head losses accordingly.
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
Atmospheric turbulent layer simulation for cfd unsteady inlet conditionsStephane Meteodyn
The aim of this work is to bridge the gap between experimental approaches in wind tunnel testing and numerical computations, in the field of structural design against strong winds. This paper focuses on the generation of an unsteady flow field, representative of a natural wind field, but still compatible with CFD inlet requirements. A simple and “naïve” procedure is explained, and the results are successfully compared to some standards.
Static analysis of c s short cylindrical shell under internal liquid pressure...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
Static analysis of c s short cylindrical shell under internal liquid pressure...eSAT Journals
Abstract The static analysis of C-S short cylindrical shell under internal liquid pressure is presented. Pasternak’s equation was adopted as the governing differential equation for cylindrical shell. By satisfying the boundary conditions of the C-S short cylindrical shell in the general polynomial series shape function, a particular shape function for the shell was obtained. This shape function was substituted into the total potential energy functional of the Ritz method, and by minimizing the functional, the unknown coefficient of the particular polynomial shape function was obtained. Bending moments, shear forces and deflections of the shell were determined, and used in plotting graphs for cases with a range of aspect ratios, 1 ≤ L/r ≤ 4. For case 1, the maximum deflection was 8.65*10-4metres, maximum rotation was 3.06*10- 3radians, maximum bending moment was -886.45KNm and maximum shear force was -5316.869KN. For case 2, the maximum deflection was 2.18*10-4metres, maximum rotation was 7.74*10-4radians, maximum bending moment was -223.813KNm and maximum shear force was -1342.878KN. For case 3, the maximum deflection was 9.71*10-5metres, maximum rotation was 3.44*10-4radians, maximum bending moment was -99.463KNm and maximum shear force was -596.779KN. For case 4,the maximum deflection was 5.48*10-5metres, maximum rotation was 1.94*10- 4radians, maximum bending moment was -56.097KNm and maximum shear force was -336.584KN. It was observed that as the aspect ratio increases from 1 to 4, the deflections, bending moments and shear forces decreases, and the shell tends to behave like long cylindrical shell. Keywords: Static analysis, Short Cylindrical Shell, internal liquid pressure, Polynomial series shape function, Boundary condition, Ritz method.
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.
Performance, Optimization and CFD Analysis of Submersible Pump Impellerijsrd.com
To improve the efficiency of submersible flow pump, Computational Fluid Dynamics (CFD) analysis is one of the advanced tools used in the pump industry. A detailed CFD analysis was done to predict the flow pattern inside the impeller which is an active pump component. From the results of CFD analysis, the velocity and pressure in the outlet of the impeller is predicted. CFD analyses are done using ANSYS CFX software. In this research paper we will modified the impeller design by choosing some parameter.
Numerical Investigation of Flow Field Behaviour and Pressure Fluctuations wit...Mustansiriyah University
this present work, CFD numerical method is applied to analyses the flow field in
an axial flow pump qualitative and quantitative analyses. Qualitative analysis for these
parameters comprise static pressure variations, dynamic pressure variations, velocity magnitude,
turbulent kinetic energy, shear stress. Quantitative analysis including the pressure fluctuations in
frequency domain analysis under different operation conditions. Also, sliding mesh method and
turbulence model type k- epsilon are used. Various monitoring points are stalled in order to
analyses pressure fluctuation mechanism in the impeller blade. The numerical results revealed
that the flow field for pressure and velocity are increase start from the suction side of the pump
to discharge side. Also, the results found that the high pressure occurs at the discharge side
along the axial direction of the impeller. The maximum value of pressure fluctuations is
occurred at tip blade region due to high interaction flow at this particular area. Moreover, the
pressure decreases as flow rate in the pump increases. Additionally, the results shown that the
pressure fluctuations have four peaks and four valleys the similar impeller blades number.
Furthermore, there are different positive and negative pressure regions, the negative pressure
area occurs due to lower pressure zone at inlet impeller area and hence which can lead to cause
occurrence of cavitation in this specific area. The current numerical demonstration results can
help the researches for further axial flow pump design.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
EFFECT OF DIFFUSER LENGTH ON PERFORMANCE CHARACTERISTICS OF ELBOW DRAFT TUBE ...IAEME Publication
The hydraulic turbines extract the energy of flowing water and converts into mechanical energy. The reaction turbine has components namely casing, stay ring, guide vane, runner and draft tube. Each component plays some role in performance of turbine. Out of above component casing, stay ring and distributor guide the flow while in runner and draft tube energy transfer and conversion takes place. In reaction turbine, significant part of input energy goes out of runner unutilized in form of kinetic energy. Draft tube are provided at exit of runner to connect turbine and tail race providing closed conduit flow of varying cross sectional area.
A REVIEW ON IMPROVEMENT OF EFFICIENCY OF CENTRIFUGAL PUMP THROUGH MODIFICATIO...ijiert bestjournal
The paper reviews the literature available on the i mprovement of efficiency of centrifugal pump through modification in suction manifolds. The paper discusses the available material of performance improvement through various paramete rs and mainly focuses on the research related to manifold modifications.
Cavitation Effects in Centrifugal Pumps- A ReviewIJERA Editor
Cavitation is one of the most challenging fluid flow abnormalities leading to detrimental effects on both the
centrifugal pump flow behaviors and physical characteristics. Centrifugal pumps’ most low pressure zones are the
first cavitation victims, where cavitation manifests itself in form of pitting on the pump internal solid walls,
accompanied by noise and vibration, all leading to the pump hydraulic performance degradation. In the present
article, a general description of centrifugal pump performance and related parameters is presented. Based on the
literature survey, some light were shed on fundamental cavitation features; where different aspects relating to
cavitation in centrifugal pumps were briefly discussed.
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.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
EXPERIMENTAL STUDIES ON THE INTAKE PORT OF A DIESEL ENGINE TO DETERMINE SWIRLijmech
This paper focuses on experimentalstudies of intake port of a four cylinder diesel engine for different
vacuum pressures and valve lift positions. In this study, the cylinder head is experimented through a paddle
wheel flow setup, which gives the flow coefficient and swirl number asoutput. Main scope of the work is to
understand the flow behaviour through the intake port and finally to determine mean flow coefficient and
mean swirl number for different valve lift ratios L/D, where L is valve lift and D is bore diameter.
The flow through the turbine components is associated with energy losses and hence energy
output from turbine is always less than the input energy. The global performance of turbine is
characterized by its overall efficiency. The casing has spiral shape and hence has swirling flow and
flow is subjected to frictional and vortex losses. The passage in stay ring and distributor has solid
vanes and flow passes through the ducts between the vanes is subjected mostly frictional losses.
Since runner is the most important component of mixed flow turbine and its design i.e. the blade
profile, number of blades plays vital role in overall performance of turbine at all operating regimes.
In the present work the numerical simulation of hydraulic Francis turbine is carried out by using
ANSYS software. The losses in each part of turbine are computed at different operating conditions
by changing the solidity of existing runner. The numerical results for efficiency of existing runner
are validated with experimental values. This study can be used efficiently as a reliable tool for
the practical design and performance analysis of Francis hydraulic turbines.
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
Industrial Training at Shahjalal Fertilizer Company Limited (SFCL)MdTanvirMahtab2
This presentation is about the working procedure of Shahjalal Fertilizer Company Limited (SFCL). A Govt. owned Company of Bangladesh Chemical Industries Corporation under Ministry of Industries.
Automobile Management System Project Report.pdfKamal Acharya
The proposed project is developed to manage the automobile in the automobile dealer company. The main module in this project is login, automobile management, customer management, sales, complaints and reports. The first module is the login. The automobile showroom owner should login to the project for usage. The username and password are verified and if it is correct, next form opens. If the username and password are not correct, it shows the error message.
When a customer search for a automobile, if the automobile is available, they will be taken to a page that shows the details of the automobile including automobile name, automobile ID, quantity, price etc. “Automobile Management System” is useful for maintaining automobiles, customers effectively and hence helps for establishing good relation between customer and automobile organization. It contains various customized modules for effectively maintaining automobiles and stock information accurately and safely.
When the automobile is sold to the customer, stock will be reduced automatically. When a new purchase is made, stock will be increased automatically. While selecting automobiles for sale, the proposed software will automatically check for total number of available stock of that particular item, if the total stock of that particular item is less than 5, software will notify the user to purchase the particular item.
Also when the user tries to sale items which are not in stock, the system will prompt the user that the stock is not enough. Customers of this system can search for a automobile; can purchase a automobile easily by selecting fast. On the other hand the stock of automobiles can be maintained perfectly by the automobile shop manager overcoming the drawbacks of existing system.
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
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.
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
Vaccine management system project report documentation..pdfKamal Acharya
The Division of Vaccine and Immunization is facing increasing difficulty monitoring vaccines and other commodities distribution once they have been distributed from the national stores. With the introduction of new vaccines, more challenges have been anticipated with this additions posing serious threat to the already over strained vaccine supply chain system in Kenya.
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
TECHNICAL TRAINING MANUAL GENERAL FAMILIARIZATION COURSEDuvanRamosGarzon1
AIRCRAFT GENERAL
The Single Aisle is the most advanced family aircraft in service today, with fly-by-wire flight controls.
The A318, A319, A320 and A321 are twin-engine subsonic medium range aircraft.
The family offers a choice of engines
The effect of rotational speed variation on the velocity vectors in the single blade passage centrifugal pump (part 2)
1. IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE)
e-ISSN: 2278-1684,p-ISSN: 2320-334X, Volume 9, Issue 2 (Sep. - Oct. 2013), PP 43-52
www.iosrjournals.org
www.iosrjournals.org 43 | Page
The effect of rotational speed variation on the velocity vectors in
the single blade passage centrifugal pump (part 2)
Dr. Mohammed Ali Mahmood Hussein, Dr. Wajeeh Kamal Hasan
Al-Rafidain University Collage,
Al-Rafidain University Collage
Abstract: 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.
Keywords: CFD, Centrifugal pump, 3D numerical simulation
I. Introduction:-
Computational fluid dynamics (CFD) analysis is being increasingly applied in the design of centrifugal
pumps. With the aid of the CFD approach, the complex internal flows in water pump impellers, which are not
fully understood yet, can be well predicted, to speed up the pump design procedure. Thus, CFD is an very
important tool for pump designers. The use of CFD tools in turbo machinery industry is quite common today.
Many tasks can numerically be solved much faster and cheaper than by means of experiments.
The complex flow pattern inside a centrifugal pump is strong three-dimensional with recirculation
flows at inlet and exit, flow separation, cavitation's, and so on. The curvature of the blades and the rotational
system have great influence on the flow field.
Dr. Jalal M. Jalil ,et al. [1] developed a solution method to obtain three-dimensional velocity and
pressure distribution within a centrifugal pump impeller. The method is based on solving fully elliptic partial
differential equations for the conservation of mass and momentum by finite difference method to convert them
into algebraic equations. The effect of turbulence introduced using a certain algebraic model based on modified
Prandtl’s mixing length theorem, Liu et al. [2], Zhou, W. et al, [3] have used a CFD code to study three-
dimensional turbulent flow through water-pump impellers during design and off-design conditions. Three
different types of centrifugal pumps were considered in this simulation. One pump had four straight blades and
the other two had six twisted blades. It was found that pumps having six twisted blades were better than those
for pumps with straight blades, which suggests that the efficiency of pumps with twisted blades will also be
higher than that of pumps with straight blades Akhras et al. [4], and Pedersen et al. [5] have made the
measurement on centrifugal pumps and reported that impeller flow separation was observed on blade surface at
off-design flow rate as compared to smooth flow within the impeller passage at design point. The numerical
simulation made by Heilmann and Siekmann [6] and Majidi and Siekmann [7] showed the strong secondary
flow in volute and circular casings of centrifugal pumps. Ziegler et al. [8], Shi and Tsukamoto [9], Shum et al.
[10], and Akhras et al. [11] studied impeller diffuser interaction on the pump performance and showed that a
strong pressure fluctuation is due to the unsteadiness of the flow shedding from impeller exit.
Hong and Kang [12] and Hagelstein et al. [13] investigated the flow field at the impeller exit and volute
separately to study the pressure distribution due to impeller-volute interaction. Traditional method to design the
centrifugal pump is mainly based on the steady-state theory, empirical correlation, combination of model
testing, and engineering experience [14]. However, to further improve the pump performance for design and off-
design operating conditions, it will become extremely difficult. Complex flow field such as the boundary layer
separation, vortex dynamics, interactions between the impeller and diffuser are difficult to control due to the
rotating and stationary components.
Zhang et al. [15, 16] found that jet-wake structure occurs near the outlet of the impeller and it is
independent of flow rate and locations. Byskov et al. [17] investigated a six-bladed impeller with shroud by
using the large eddy simulation (LES) at design and off-design conditions. At design load, the flow field inside
2. The effect of rotational speed variation on the velocity vectors in the single blade passage centrifugal
www.iosrjournals.org 44 | Page
the impeller is smooth and with no significant separation. At quarter design load, a steady nonrotating stall
phenomenon is observed in the entrance and a relative eddy is developed in the remaining of the passage. Gu et
al. [18] also investigated the volute/diffuser interaction of a single stage centrifugal compressor at design point
and off-design. At higher flow rate, a twin vortex structure is formed downstream of the passage.
The recirculation and the twin vortex structure are attributed increase of the total pressure losses at off-
design conditions. Hence with the advancing of computer power, significant improvement of numerical
algorithms and more reliable CFD codes, it can be seen that there is an increasing trend of applying numerical
methods to study the complex flow
II. Governing equations:-
Casting of The three-dimensional and incompressible flow in the pumps can be described with the
conservations laws of movement and mass in cylindrical coordinates for radial (r) , angular (θ) and axial (z)
directions. In terms of the divergence theorem, the continuity equation or conservation mass,
Continuity: [17]:
(1)
Momentum:
(2)
where: ρ = density fluid
= vector velocity absolute
μef =viscosity effective fluid
P= pressure body forces
Fi = the additional sources of momentum
Since the momentum equations are considered in a relative reference frame associated to the rotor blade, the
Coriolis force and centrifugal forces are added as a momentum source term:
(3)
Where
(4)
(5)
ωi : is angular velocity
εijk is Levi-Civita third order tensor
III. Turbulence model
The left side term in Equation (2) represents the convective acceleration. The right side terms represent the
pressure gradient, the viscous effects and the source terms respectively. The turbulence model chosen was the k-
ε model due to its stability, widespread application in commercial software's and robustness. The k-ε model and
its extensions resolve the partial differential equations for turbulent kinetic energy k and the dissipation rate ε as
shown by the Equations (6) and (7):
(6)
(7)
Where the diffusion coefficients are given by
(8)
and
(9)
The turbulence viscosity, μt can be derived from Eq. (9) and (10), to link to the turbulence kinetic energy
and dissipation via the relation
(10)
3. The effect of rotational speed variation on the velocity vectors in the single blade passage centrifugal
www.iosrjournals.org 45 | Page
And
(11)
(12)
Pk is the term for the production of turbulence due to viscous forces Parameter values considered in the
simulations are presented in the table 1.
Table 1: Parameters for modeling the k- ε model
Equations (1), (2), (6), and (7) form a closed set of nonlinear partial differential equations governing the
fluid motion.
All the previous equations are valid both for the impeller and for the diffuser; however the rotational
forces in the source terms will only apply for the impeller in the movement equation as a result of Coriolis
forces and centrifugal forces.The transport equations associated with the given boundaries conditions describing
the internal flow in centrifugal pump are solved by the (ANSYS-CFX, 2012) code.
IV. Single passage, Geometry and Grid
With the three-dimensional model there is a useful approach for investigation of flow behavior in different
parts of pump. Figure 1shows the centrifugal pump geometry and structured grid generated of single blade
passage (blade mesh, hub mesh, and shroud mesh). Problem consists of a five blade centrifugal pump operating
at 2100 rpm. The working fluid is water and flow is assumed to be steady and incompressible .Due to rotational
periodicity a single blade passage will be modeled. Table (2) Operating conditions
Description Value
Density of fluid 1000 kg/m3
Viscosity 0.0017 kg/m*s
Rotational speed 2100 rpm
(a) Centrifugal pump geometry (b) Single blade passage geometry and mesh
(c) Blade mesh (d) Hub Mesh (e)Shroud mesh
Figure (1) (a,b.c.d.e) Shows the Centrifugal pump and generated mesh
4. The effect of rotational speed variation on the velocity vectors in the single blade passage centrifugal
www.iosrjournals.org 46 | Page
V. Results And Discussions
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 in
the centrifugal pump . Figures (2,3&4) represent the vectors of the velocity of the blade, hub, and shroud at
rotational speed of 1800 rpm the flow indicates low velocity vectors (4.03×10-1
m/s) in the suction side
and the velocity vectors increases gradually until reach maximum value at the leading edge (1.79×10 m/s) .
Figure(2) Velocity vectors in (Z-Y)plane of blade at 1800rpm
Figure(3) Velocity vectors in (X-Y)plane of hub at 1800rpm
Figure(4) Velocity vectors contours in (X-Y)plane of shroud at 1800rpm
Figures (5,6&7) represent the contours of the velocity vectors of the blade, hub, and shroud at rotational speed
of 1900 rpm the flow indicates constant velocity vectors (4.03×10-1
m/s) in the suction side which is same as
5. The effect of rotational speed variation on the velocity vectors in the single blade passage centrifugal
www.iosrjournals.org 47 | Page
the above case and then the velocity vectors increases gradually until reach maximum value at the leading edge
(1.93×10 m/s) which is larger than the value in the above case .
Figure(5) Velocity vectors in (Z-Y)plane of blade at 1900rpm
Figure(6) Velocity vectors in (X-Y)plane of hub at 1900rpm
Figure(7) Velocity vectors in (X-Y)plane of shroud at 1900rpm
Figures (8,9&10) represent the vectors of the velocity of the blade, hub, and shroud at rotational speed of
2000rpm the flow indicates constant velocity vectors (4.03×10-1
m/s) in the suction side which is same as the
above cases and then the velocity vectors increases gradually until reach maximum value at the leading edge
(2.07×10 m/s) which is larger than the value in the above case .
6. The effect of rotational speed variation on the velocity vectors in the single blade passage centrifugal
www.iosrjournals.org 48 | Page
Figure(8) Velocity vectors in (Z-Y)plane of blade at 2000rpm
Figure(9) Velocity vectors in (X-Y)plane of hub at 2000rpm
Figure(10) Velocity vectors in (X-Y)plane of shroud at 2000rpm
Figures from (11) to (16) represent the velocity vectors of the blade, hub, and shroud at rotational speed of
2100rpm and 2200 rpm which is the operation conditions (design point) flow indicates approximately constant
velocity vectors (4.02×10-1
m/s) in the suction side which is same as the above cases and then the velocity
vectors increases gradually until reach maximum value at the leading edge (2.36×10 m/s) which is larger than
the value in the above cases .
7. The effect of rotational speed variation on the velocity vectors in the single blade passage centrifugal
www.iosrjournals.org 49 | Page
Figure(11) Velocity vectors in (Z-Y)plane of blade at 2100rpm
Figure(12) Velocity vectors in (X-Y)plane of hub at 2100rpm
Figure(13) Velocity vectors in (X-Y)plane of shroud at 2100rpm
8. The effect of rotational speed variation on the velocity vectors in the single blade passage centrifugal
www.iosrjournals.org 50 | Page
Figure(14) Velocity vectors in (Z-Y)plane of blade at 2200rpm
Figure(15) Velocity vectors in (X-Y)plane of hub at 2200rpm
Figure(16) Velocity vectors in (X-Y)plane of shroud at 2200rpm
Figures from (17) to (22) represent the velocity vectors of the blade, hub, and shroud at rotational speed of
2300rpm and 2400 rpm which is over the operation conditions (overload) flow indicates increases gradually
until reach maximum value at the leading edge (2.63×10 m/s) which is larger than the value in the above cases.
Figure(17) Velocity vectors in (Z-Y)plane of blade at 2300rpm
9. The effect of rotational speed variation on the velocity vectors in the single blade passage centrifugal
www.iosrjournals.org 51 | Page
Figure(18) Velocity vectors in (X-Y)plane of hub at 2300rpm
Figure(19) Velocity vectors in (X-Y)plane of shroud at 2300rpm
Figure(20) Velocity vectors in (Z-Y)plane of blade at 2400rpm
Figure(21) Velocity vectors in (X-Y)plane of hub at 2400rpm
10. The effect of rotational speed variation on the velocity vectors in the single blade passage centrifugal
www.iosrjournals.org 52 | Page
Figure(22) Velocity vectors in (X-Y)plane of shroud at 2400rpm
VI. Conclusion
The complex three dimensional internal flow field of the centrifugal pump is investigated by using
numerical methods .This centrifugal pump simulation has permitted to study the internal flow velocity vectors
distribution of the pump operating at variable rotational speed (under and over operation limits). The analysis of
all the above results have led to the following conclusion:-
Flow indicates approximately constant velocity vectors (4.02×10-1
m/s) in the suction side.
The velocity vectors increases gradually until reach maximum value at the leading edge.
At the high rotational speed over the design point the velocity vectors in the leading edge increases until
reaches maximum value(2.63×10 m/s).
References
[1] Dr. Jalal M. Jalil, Dr. Khalaf H. Ali, Dr. Hussein M. al-Yassiri, Three--Dimensional Numerical Study of Flow Characteristics
Through a Centrifugal Pump, Al-Rafidain Engineering Vol.16 No.1 2008.
[2] C. H. Liu, C. Vafidis, and J. H.Whitelaw, ―Flow characteristics of a centrifugal pump,‖ ASME Journal of Fluids Engineering, vol.
116, no. 2, pp. 303–309, 1994.
[3] Zhou, W., Zhao, Z., Lee, T. S., and Winoto, S. H., Investigation of flow through centrifugal pump impellers using computational fluid
dynamics, International Journal of Rotating Machinery, volume 9, pp 49–61.2003.
[4] A. Akhras, M. El Hajem, R. Morel, and J.-Y. Champagne, ―Internal flow investigation of a centrifugal pump at the design point,‖
Journal of Visualization, vol. 4, no. 1, pp. 91–98, 2001.
[5] N. Pedersen, P. S. Larsen, and C. B. Jacobsen, ―Flow in a centrifugal pump impeller at design and off-design conditions— part I:
particle image velocimetry (PIV) and laser Doppler velocimetry (LDV) measurements,‖ ASME Journal of Fluids Engineering, vol.
125, no. 1, pp. 61–72, 2003.
[6] C. M. Heilmann and H. E. Siekmann, ―Particle image velocimetry as CFD validation tool for flow field investigation in centrifugal
pumps,‖ in Proceedings of the 9th International Symposium on Transport Phenomena and Dynamics of Rotating Machinery
(ISROMAC ’02),Honolulu,Hawaii, USA, February 2002.
[7] K. Majidi and H. E. Siekmann, ―Numerical calculation of secondary flow in pump volute and circular casings using 3D viscous flow
techniques,‖ International Journal of Rotating Machinery, vol. 6, no. 4, pp. 245–252, 2000.
[8] K. U. Ziegler, H. E. Gallus, and R. Niehuis, ―A study on impeller-diffuser interaction—part I: influence on the performance,‖ Journal
of Turbomachinery, vol. 125, no. 1, pp. 173–182, 2003.
[9] F. Shi and H. Tsukamoto, ―Numerical study of pressure fluctuations caused by impeller-diffuser interaction in a diffuser pump stage,‖
ASME Journal of Fluids Engineering, vol. 123, no. 3, pp. 466–474, 2001.
[10] Y. K. P. Shum,C. S.Tan, andN. A. Cumpsty, ―Impeller-diffuser interaction in a centrifugal compressor,‖ Journal of Turbomachinery,
vol. 122, no. 4, pp. 777–786, 2000.
[11] A. Akhras, M. El Hajem, J.-Y. Champagne, and R.Morel, ―The flow rate influence on the interaction of a radial pump impeller and
the diffuser,‖ International Journal of Rotating Machinery, vol. 10, no. 4, pp. 309–317, 2004.
[12] S.-S. Hong and S.-H. Kang, ―Flow at the centrifugal pump impeller exit with circumferential distortion of the outlet static pressure,‖
ASME Journal of Fluids Engineering, vol. 126, no. 1, pp. 81–86, 2004.
[13] D. Hagelstein, K. Hillewaert, R. A. Van den Braembussche, A. Engeda, R. Keiper, andM. Rautenberg, ―Experimental and numerical
investigation of the flow in a centrifugal compressor volute,‖ Journal of Turbomachinery, vol. 122, no. 1, pp. 22–31,2000.
[14] A. J. Stepanoff, Centrifugal and Axial Flow Pumps: Theory, Design and Application, Krieger, Melbourne, Fla, USA, 2nd edition,
1992.
[15] M.-J. Zhang, M. J. Pomfret, and C. M. Wong, ―Three dimensional viscous flow simulation in a backswept centrifugal impeller at the
design point,‖ Computers and Fluids, vol. 25, no. 5, pp. 497–507, 1996.
[16] M.-J. Zhang, M. J. Pomfret, and C. M. Wong, ―Performance prediction of a backswept centrifugal impeller at off-design point
conditions,‖ International Journal for Numerical Methods in Fluids, vol. 23, no. 9, pp. 883–895, 1996.
[17] R. K. Byskov, C. B. Jacobsen, and N. Pedersen, ―Flow in a centrifugal pump impeller at design and off-design conditions— part II:
large eddy simulations,‖ ASME Journal of Fluids Engineering, vol. 125, no. 1, pp. 73–83, 2003.International IBPSA Conference, Rio
de Janeiro, Brazil, pp. 1135-1141.
[18] F. Gu, A. Engeda, M. Cave, and J.-L. Di Liberti, ―A numerical investigation on the volute/diffuser interaction due to the axial
distortion at the impeller exit,‖ ASME Journal of Fluids Engineering, vol. 123, no. 3, pp. 475–483, 2001.