This document discusses a numerical study on the effect of jet shape on the flow and torque characteristics of a Pelton turbine runner. Four different jet shapes - circular, triangular, square and elliptical - were simulated using computational fluid dynamics (CFD) software, keeping the cross-sectional area of the jets constant. The results showed that the circular jet produced the highest hydraulic efficiency of 88.03%, distributing water most uniformly across the buckets. The triangular and square jets did not allow complete emptying of buckets before the next jet arrived, reducing efficiency. The elliptical jet had the lowest efficiency of 77.80%. In conclusion, circular jets were found to be most efficient for Pelton turbines.
Jet pump is a type of mechanical device where the extra energy is provide by jet in mixing chamber. This jet is the fluid again circulate from diffuser exit to mixing chamber for better performance. This is also known as motive fluid. So the effects of change in geometrical parameter (Diffuser angle) on its performance were investigated. The set of experiment were carried out to study the effect of diffuser angle on the performance of jet pump. The performance of the jet pump is described by three sets of curves, Discharge vs. Head, Input power vs. Head, and Efficiency vs. Head. Changing the diffuser angle will affect jet pump behavior. Venturi diffuser angle was found to be an important geometrical parameter to characterize the maximum suction lift of the jet pump.
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.
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.
Jet pump is a type of mechanical device where the extra energy is provide by jet in mixing chamber. This jet is the fluid again circulate from diffuser exit to mixing chamber for better performance. This is also known as motive fluid. So the effects of change in geometrical parameter (Diffuser angle) on its performance were investigated. The set of experiment were carried out to study the effect of diffuser angle on the performance of jet pump. The performance of the jet pump is described by three sets of curves, Discharge vs. Head, Input power vs. Head, and Efficiency vs. Head. Changing the diffuser angle will affect jet pump behavior. Venturi diffuser angle was found to be an important geometrical parameter to characterize the maximum suction lift of the jet pump.
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.
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.
STRUCTURAL AND VIBRATIONAL RESPONSE ANALYSIS OF H.P. BLADED DISC ASSEMBLYIAEME Publication
In this article, an effort has been made to deal with structural behavior of the Steam turbine HP blade and disc assembly rotating at 100% (6000 rpm) optimum speed and 120% (7200rpm) over speed conditions which in turn create large amount of centrifugal force. This is the dominating force in steam turbine blade assembly which is the cause for all its behavior. Vibrational analysis of this HP blade and disc assembly is also carried out using FEA methods to determine and predict the fatigue life of the blade and disc. The Structural analysis is carried out on the HP blade and disc to understand the Structural behaviors which comes on them in order to find out the factor of safety of the HP blade and disc assembly due to high angular velocity.
THE EFFECT OF VARIATION SKEW ANGLE B-SERIES PROPELLER ON PERFORMANCE AND CAVI...IAEME Publication
Achieving the highest possible efficiency from a propeller is needed to minimize
fuel. However, this is limited by the occurrence of cavitation, vibration, noise and
material strength possessed by propellers. Thus it is necessary to do a new
breakthrough in designing or modifying the shape of the propeller to achieve
maximum performance. One modification that can be done is to change the skew
angle. Propeller B-Series is a propeller that is often used and has a fairly complete
geometry data. Cavitation is something that must be considered because it will
manifest into noise, vibration and erosion in the propeller blade. The modification of
the skew angle will be analyzed using the CFD (Computational Fluid Dynamics)
method of how the relationship between performance and cavitation results from the
various variations that have been made. So that later it can be known that skew angles
produce maximum performance and low cavitation. From the simulation results it can
be concluded that the greater the skew angle, the value of the thrust and torque
Knowledge Based Design of Axial Flow CompressorIJERA Editor
In the aerospace industry with highly competitive market the time to design and delivery is shortening every day. Pressure on delivering robust product with cost economy is in demand in each development. Even though technology is older, it is new for each customer requirement and highly non-liner to fit one in another place. Gas turbine is considered one of a complex design in the aircraft system. It involves experts to be grouped with designers of various segments to arrive the best output. The time is crucial to achieve a best design and it needs knowledge automation incorporated with CAD/CAE tools. In the present work an innovative idea in the form of Knowledge Based Engineering for axial compressor is proposed, this includes the fundamental design of axial compressor integrated with artificial intelligence in the form of knowledge capturing and programmed with high level language (Visual Basis.Net) and embedded into CATIA v5. This KBE frame work eases out the design and modeling of axial compressor design and produces 3D modeling for further flow simulation with fluid dynamic in Ansys-Fluent. Most of the aerospace components are developed through simulation driven product development and in this case it is established for axial compressor.
fatigue failure analysis of steam turbine shaft using fem techniqueIjripublishers Ijri
The aim of the project is to locate best constrain location by evaluating steam turbine shaft with different materials.
Initially data collection will be done to understand rectification methodology and approach.
A 3D model of shaft will be prepared and exported into IGES (inertial graphical exchanging specifications) format to
conduct further work in ANSYS.
Structural analysis will be carried out on assembly to evaluate structural characteristics.
Model analysis will be carried out on same to find natural frequency’s (for comparison with other results)
Thermal analysis will be carried out on to find thermal characteristic.
Comparison tables will be prepared according to the obtained results from Ansys; Conclusion will be made according
to the obtained results.
Key words: steam turbine, shaft, hollow shaft,fatigue failure analysis.
The HAWTs are existed in different sizes and they used in a different
requirements depending on the applications
HAWT in scale of 1:6.5 of original model was presented. The scale model of HAWT
and a suitable diffuser as a shroud for its, were fabricated and experimented in
wind tunnel in two forms, bare
were conducted using a new method to power calculation at a different wind velocities
ranged 5 - 9 m/s with focusing on a two wind speeds, 7 m/s and 8 m
tests in terms of power coefficient
an increasing in the power coefficient of the shrouded HAWT model
1.52 compare to the bare model one. On another hand, the experiments results were
validated with CFD simulation results for all cases
Moreover, CFD provided a clear visualization for the flow across wind turbine.
DEVELOPMENT AND TESTING OF ADVANCE HYBRID SAVONIUS AND ARM GEAR BASED STRUCTU...IAEME Publication
Wind energy is becoming the most important renewable source in terms of globally installed capacity, after solar and hydro power. China is experiencing a rapid expansion in the wind power industry. This paper provides a good overview of the current status and future development of wind generation. As per the technical evolution and technical trends consideration so we have created a “Advanced Hybrid Savonius and arm gear based effective Mechanical Structure for Multi-Station Optimized Power Generation. This system uses an advanced savonius hybrid turbine which will rotate over multiple natural resources water force, wind power and related parameters having efficiency greater than aerodynamic turbine.
ADVANCED TRANSIENT THERMAL AND STRUCTURAL ANALYSIS OF DISC BRAKE BY USING ANS...ijiert bestjournal
In these paper structural fields of the solid disc brake during short and emergency braking with four different materials is studied. The distribution of the tempe rature depends on the various factors such as frict ion,surface roughness and speed. The effect of the angular velo city and the contact pressure induces the temperatu re rise of disc brake. The finite element simulation for three -dimensional model was preferred due to the heat fl ux ratio constantly distributed in circumferential direction . Here value of temperature,friction contact power,nodal displacement and deformation for different pressure condition using analysis software with four materi als namely cast iron,cast steel,aluminium and carbon fibre reinforced plastic are taken. Presently the D isc brakes are made up of cast iron and cast steel. With the v alue of simulation result best suitable material fo r the brake drum with higher life span is determined.
Design of Naca63215 Airfoil for a Wind TurbineIOSR Journals
The ultimate objective of the work is to increase the reliability of wind turbine blades through the development of the airfoil structure and also to reduce the noise produced during the running period of the wind turbine blades. The blade plays a pivotal role, because it is the most important part of the energy absorption system. Consequently, the blade has to be designed carefully to enable to absorb energy with its greatest efficiency. In this work, Pro/E, Hypermesh software has been used to design blades effectively. NACA 63-215 airfoil profile is considered for analysis of wind turbine blade. The wind turbine blade is modeled and several sections are created from root to tip with the variation from the standard design for improving the efficiency. For the further improvement required in the efficiency of the wind turbine the winglet is to be included at the tip of the blade which would help in increasing the efficiency and reducing the noise produced from the blades in working condition. The existing turbine blade and the modified blade with the winglet are compared for their results.
Transient flow analysis for horizontal axial upper-wind turbineinventy
This study is to carry out a transient flow field analysis on the condition that the wind turbine is working to generate turbine, the wind turbine operating conditions change over time, Purpose of this study is try to find out the rule from the wind turbine changing over time . In transient analysis, the wind velocity on inlet boundary and rotation speed in the rotor field will change over time, and an analytical process is provided that can be used for future reference. At present, the wind turbine model is designed on the concept of upwind horizontal axis type. The computer engineering software GH Bladed is used to obtain the relationship between the rotor velocity and the wind turbine. Then the ANSYS engineering software is used to calculate the stress and strain distribution in the blades over time. From the analytical result, the relationship between the stress distribution in the blades and the rotor velocity is got to be used as a reference for future wind turbine structural optimization.
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.
THERMAL & STRUCTURAL ANALYSIS ON DISC BRAKE ROTOR WITH DRAFTING USING CATIA ...NitinSuryawanshi12
Project consist of two types of analysis thermal , structural & VBA Programming.
Thermal analysis is done to check the thermal resistance of model Honda Unicorn 160.
Structural analysis is done to find the strength of the model.
VBA programming is used to automate drafting task.
Runner profile optimisation of gravitational vortex water turbine IJECEIAES
This study discusses the numerical optimisation and performance testing of the turbine runner profile for the designed gravitational water vortex turbine. The initial design of the turbine runner is optimised using a surface vorticity algorithm coded in MATLAB to obtain the optimal stagger angle. Design validation is carried out using computational fluid dynamics (CFD) Ansys CFX to determine the performance of the turbine runner with the turbulent shear stress transport model. The CFD analysis shows that by optimising the design, the water turbine efficiency increases by about 2.6%. The prototype of the vortex turbine runner is made using a 3D printing machine with resin material. It is later tested in a laboratory-scale experiment that measures the shaft power, shaft torque and turbine efficiency in correspondence with rotational speeds varying from 150 to 650 rpm. Experiment results validate that the optimised runner has an efficiency of 45.3% or about 14% greater than the initial design runner, which has an efficiency of 39.7%.
STRUCTURAL AND VIBRATIONAL RESPONSE ANALYSIS OF H.P. BLADED DISC ASSEMBLYIAEME Publication
In this article, an effort has been made to deal with structural behavior of the Steam turbine HP blade and disc assembly rotating at 100% (6000 rpm) optimum speed and 120% (7200rpm) over speed conditions which in turn create large amount of centrifugal force. This is the dominating force in steam turbine blade assembly which is the cause for all its behavior. Vibrational analysis of this HP blade and disc assembly is also carried out using FEA methods to determine and predict the fatigue life of the blade and disc. The Structural analysis is carried out on the HP blade and disc to understand the Structural behaviors which comes on them in order to find out the factor of safety of the HP blade and disc assembly due to high angular velocity.
THE EFFECT OF VARIATION SKEW ANGLE B-SERIES PROPELLER ON PERFORMANCE AND CAVI...IAEME Publication
Achieving the highest possible efficiency from a propeller is needed to minimize
fuel. However, this is limited by the occurrence of cavitation, vibration, noise and
material strength possessed by propellers. Thus it is necessary to do a new
breakthrough in designing or modifying the shape of the propeller to achieve
maximum performance. One modification that can be done is to change the skew
angle. Propeller B-Series is a propeller that is often used and has a fairly complete
geometry data. Cavitation is something that must be considered because it will
manifest into noise, vibration and erosion in the propeller blade. The modification of
the skew angle will be analyzed using the CFD (Computational Fluid Dynamics)
method of how the relationship between performance and cavitation results from the
various variations that have been made. So that later it can be known that skew angles
produce maximum performance and low cavitation. From the simulation results it can
be concluded that the greater the skew angle, the value of the thrust and torque
Knowledge Based Design of Axial Flow CompressorIJERA Editor
In the aerospace industry with highly competitive market the time to design and delivery is shortening every day. Pressure on delivering robust product with cost economy is in demand in each development. Even though technology is older, it is new for each customer requirement and highly non-liner to fit one in another place. Gas turbine is considered one of a complex design in the aircraft system. It involves experts to be grouped with designers of various segments to arrive the best output. The time is crucial to achieve a best design and it needs knowledge automation incorporated with CAD/CAE tools. In the present work an innovative idea in the form of Knowledge Based Engineering for axial compressor is proposed, this includes the fundamental design of axial compressor integrated with artificial intelligence in the form of knowledge capturing and programmed with high level language (Visual Basis.Net) and embedded into CATIA v5. This KBE frame work eases out the design and modeling of axial compressor design and produces 3D modeling for further flow simulation with fluid dynamic in Ansys-Fluent. Most of the aerospace components are developed through simulation driven product development and in this case it is established for axial compressor.
fatigue failure analysis of steam turbine shaft using fem techniqueIjripublishers Ijri
The aim of the project is to locate best constrain location by evaluating steam turbine shaft with different materials.
Initially data collection will be done to understand rectification methodology and approach.
A 3D model of shaft will be prepared and exported into IGES (inertial graphical exchanging specifications) format to
conduct further work in ANSYS.
Structural analysis will be carried out on assembly to evaluate structural characteristics.
Model analysis will be carried out on same to find natural frequency’s (for comparison with other results)
Thermal analysis will be carried out on to find thermal characteristic.
Comparison tables will be prepared according to the obtained results from Ansys; Conclusion will be made according
to the obtained results.
Key words: steam turbine, shaft, hollow shaft,fatigue failure analysis.
The HAWTs are existed in different sizes and they used in a different
requirements depending on the applications
HAWT in scale of 1:6.5 of original model was presented. The scale model of HAWT
and a suitable diffuser as a shroud for its, were fabricated and experimented in
wind tunnel in two forms, bare
were conducted using a new method to power calculation at a different wind velocities
ranged 5 - 9 m/s with focusing on a two wind speeds, 7 m/s and 8 m
tests in terms of power coefficient
an increasing in the power coefficient of the shrouded HAWT model
1.52 compare to the bare model one. On another hand, the experiments results were
validated with CFD simulation results for all cases
Moreover, CFD provided a clear visualization for the flow across wind turbine.
DEVELOPMENT AND TESTING OF ADVANCE HYBRID SAVONIUS AND ARM GEAR BASED STRUCTU...IAEME Publication
Wind energy is becoming the most important renewable source in terms of globally installed capacity, after solar and hydro power. China is experiencing a rapid expansion in the wind power industry. This paper provides a good overview of the current status and future development of wind generation. As per the technical evolution and technical trends consideration so we have created a “Advanced Hybrid Savonius and arm gear based effective Mechanical Structure for Multi-Station Optimized Power Generation. This system uses an advanced savonius hybrid turbine which will rotate over multiple natural resources water force, wind power and related parameters having efficiency greater than aerodynamic turbine.
ADVANCED TRANSIENT THERMAL AND STRUCTURAL ANALYSIS OF DISC BRAKE BY USING ANS...ijiert bestjournal
In these paper structural fields of the solid disc brake during short and emergency braking with four different materials is studied. The distribution of the tempe rature depends on the various factors such as frict ion,surface roughness and speed. The effect of the angular velo city and the contact pressure induces the temperatu re rise of disc brake. The finite element simulation for three -dimensional model was preferred due to the heat fl ux ratio constantly distributed in circumferential direction . Here value of temperature,friction contact power,nodal displacement and deformation for different pressure condition using analysis software with four materi als namely cast iron,cast steel,aluminium and carbon fibre reinforced plastic are taken. Presently the D isc brakes are made up of cast iron and cast steel. With the v alue of simulation result best suitable material fo r the brake drum with higher life span is determined.
Design of Naca63215 Airfoil for a Wind TurbineIOSR Journals
The ultimate objective of the work is to increase the reliability of wind turbine blades through the development of the airfoil structure and also to reduce the noise produced during the running period of the wind turbine blades. The blade plays a pivotal role, because it is the most important part of the energy absorption system. Consequently, the blade has to be designed carefully to enable to absorb energy with its greatest efficiency. In this work, Pro/E, Hypermesh software has been used to design blades effectively. NACA 63-215 airfoil profile is considered for analysis of wind turbine blade. The wind turbine blade is modeled and several sections are created from root to tip with the variation from the standard design for improving the efficiency. For the further improvement required in the efficiency of the wind turbine the winglet is to be included at the tip of the blade which would help in increasing the efficiency and reducing the noise produced from the blades in working condition. The existing turbine blade and the modified blade with the winglet are compared for their results.
Transient flow analysis for horizontal axial upper-wind turbineinventy
This study is to carry out a transient flow field analysis on the condition that the wind turbine is working to generate turbine, the wind turbine operating conditions change over time, Purpose of this study is try to find out the rule from the wind turbine changing over time . In transient analysis, the wind velocity on inlet boundary and rotation speed in the rotor field will change over time, and an analytical process is provided that can be used for future reference. At present, the wind turbine model is designed on the concept of upwind horizontal axis type. The computer engineering software GH Bladed is used to obtain the relationship between the rotor velocity and the wind turbine. Then the ANSYS engineering software is used to calculate the stress and strain distribution in the blades over time. From the analytical result, the relationship between the stress distribution in the blades and the rotor velocity is got to be used as a reference for future wind turbine structural optimization.
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.
THERMAL & STRUCTURAL ANALYSIS ON DISC BRAKE ROTOR WITH DRAFTING USING CATIA ...NitinSuryawanshi12
Project consist of two types of analysis thermal , structural & VBA Programming.
Thermal analysis is done to check the thermal resistance of model Honda Unicorn 160.
Structural analysis is done to find the strength of the model.
VBA programming is used to automate drafting task.
Runner profile optimisation of gravitational vortex water turbine IJECEIAES
This study discusses the numerical optimisation and performance testing of the turbine runner profile for the designed gravitational water vortex turbine. The initial design of the turbine runner is optimised using a surface vorticity algorithm coded in MATLAB to obtain the optimal stagger angle. Design validation is carried out using computational fluid dynamics (CFD) Ansys CFX to determine the performance of the turbine runner with the turbulent shear stress transport model. The CFD analysis shows that by optimising the design, the water turbine efficiency increases by about 2.6%. The prototype of the vortex turbine runner is made using a 3D printing machine with resin material. It is later tested in a laboratory-scale experiment that measures the shaft power, shaft torque and turbine efficiency in correspondence with rotational speeds varying from 150 to 650 rpm. Experiment results validate that the optimised runner has an efficiency of 45.3% or about 14% greater than the initial design runner, which has an efficiency of 39.7%.
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.
Performance Analysis For Reaction Turbine – A Case StudyIJERA Editor
Performance test on a model of a Francis turbine has been carried out in the laboratory for various gate opening of the turbine. The parameters have been expressed in the term of unit quantities. The result show that the peak efficiency lies between 76% and 88% of the full load. The maximum efficiency and power obtained at Nu =362, whereas maximum efficiency obtained is 74% at 95% wicket gate opening, Predicted result based on the modal study for a prototype obtained is within the specified limit.
Investigations of laminar fluid flow between two moving or stationary plates, and two rotating discs, over the years were geared toward how to increase Tesla-based turbine efficiency. Therefore, this research entails the construction, design and simulation of a Tesla turbine in order to investigate the potential of Tesla turbine for energy generation. Method of solution entails the design and construction of a physical model Tesla turbine from locally sourced materials. The physical model geometry and design parameters were then used to conduct numerical simulation. Performance evaluation was then carried on the physical model and the simulation model. The result showed that voltage, current and power all increase with increase in rev. per minute. The result obtained indicates that for higher power generation, a Tesla turbine design with higher revolution per minute capability will be required. Turbine model simulation showed that radial velocity vector to be concentrated at the discs periphery and outlet.
The research results are good references for design of larger Tesla turbine for community use.
Investigations of laminar fluid flow between two moving or stationary plates, and two rotating discs, over the years were geared toward how to increase Tesla-based turbine efficiency. Therefore, this research entails the construction, design and simulation of a Tesla turbine in order to investigate the potential of Tesla turbine for energy generation. Method of solution entails the design and construction of a physical model Tesla turbine from locally sourced materials. The physical model geometry and design parameters were then used to conduct numerical simulation. Performance evaluation was then carried on the physical model and the simulation model. The result showed that voltage, current and power all increase with increase in rev. per minute. The result obtained indicates that for higher power generation, a Tesla turbine design with higher revolution per minute capability will be required. Turbine model simulation showed that radial velocity vector to be concentrated at the discs periphery and outlet.
The research results are good references for design of larger Tesla turbine for community use.
Influence of number of impeller and diffuser blades on the pressure recovery ...eSAT Journals
Abstract Impeller is a very important element in rotating devices to deliver energy to/from the fluid. The diffusers are essential for effective transformation of the kinetic power produced by the rotor in a centrifugal fan. Hence the flow in the impeller and diffuser passages is the important phenomenon in optimizing the performance. These impeller and diffuser flow passages are the most complex regions to predict the flow behavior. With the advanced development of Particle Image Velocimetry as well as convenient numerical CFD tools, it has become possible to reach at an accurate result well-matched with the real behavior of the flow. Hence, in this work moving mesh technique is used to get a numerical solution for the estimation of actual flow manner. Numerous research works have been done recently to get the physics of fluid flow through impeller and diffuser, both numerically and experimentally. But it is found from the literature that the study on the performance of the fan by changing the number of impeller and diffuser blades together in a combination has not been the emphasis of attention in these works. Hence a numerical analysis has been carried out in this paper to comprehensively lookout the fluid interaction in impeller-diffuser as well as to envisage the flow behavior of the fan by changing the number of impeller and diffuser blades together in combination. For the same number of impeller blades, it is found from the analysis that a higher static pressure rise coefficient is achieved at the outlet of the fan for smaller number of diffuser blades. It is also found that larger the number of impeller blades, larger is the static pressure rise coefficient for the same number of diffuser blades, hence performance gets improved. Key Words: Unsteady flow, Recirculation zone, Turbulence, Impeller vane, Diffuser vane, Static pressure rise.
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.
Effect of tip clearance on performance of a centrifugal compressoreSAT Journals
Abstract The centrifugal compressor is to study the effect of tip clearance on the performance characteristics and the wall static pressure for a different flow co-efficient. The method of testing the compressor is run at a constant speed at 2000rpm. The tip clearance is varied by using spacers. The volume flow rate is varied with the help of throttling device to conduct the performance test. The performance characteristic of the centrifugal compressor showing the variation of discharge pressure with volume flow rate is plotted. Obtaining the performance characteristics showing the variation of discharge pressure with volume flow rate for different tip clearance, viz. =2.2%, 4%, 6.1% and 7.9%. Measurement of periodic pressure at various tip clearance viz. =2.2%, 4%, 6.1% and 7.9%. For each tip clearance pressure measured in radial location of impeller at 6 positions for different flow co efficient values. Five flow coefficients viz., ф =0.40, =0.34 (both above design flow), =0.28 (near design flow), =0.21=0.18 (both below design flow) and four values of non-dimensional tip clearance viz., =2.2%, 4%, 6.1% and 7.9%, are chosen for experimental work. The objective of the research work is to measure the periodic variation static pressure on the casing over the rotor at different values of tip clearance and flow coefficients. With the availability of these data, it is possible to improve the tip clearance flow in centrifugal compressor.
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
Optimization of design of mixed flow centrifugal pump impeller using cfdeSAT Journals
Abstract
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1. Vishal Gupta et al Int. Journal of Engineering Research and Applications
ISSN : 2248-9622, Vol. 4, Issue 1( Version 1), January 2014, pp. 318-323
RESEARCH ARTICLE
www.ijera.com
OPEN ACCESS
Effect of Jet Shape on Flow and Torque Characteristics of Pelton
Turbine Runner
Vishal Gupta*, Dr. Vishnu Prasad**, Dr. Ruchi Khare***
*(PhD Research Scholar, Department of Energy M.A. National Institute of Technology, Bhopal, MP, India)
** (Professor, Department of Civil Engineering M.A. National Institute of Technology, Bhopal, MP, India)
*** (Assistant Professor, Department of Civil Engineering M.A. National Institute of Technology, Bhopal, MP,
India)
ABSTRACT
In Pelton turbine, the energy carried by water is converted into kinetic energy by providing nozzle at the end of
penstock. The shape of jet affects the force and torque on the bucket and runner of turbine. The nozzle of
circular cross section is commonly used. In this paper attempt has been made to study the effect of four different
jet shapes on the flow and torque characteristics of Pelton turbine runner through numerical simulation.
Keywords - Multiphase flow, jet shape, Pelton turbine, free surface flow, nozzle
I.
INTRODUCTION
Pelton turbines are tangential flow impulse
turbines which operates under high head of water and
require comparatively less quantity of water. Water is
conveyed in penstocks from head race to the turbine
in power house. Pelton turbine consists of a circular
disc on which a number of buckets are evenly spaced
around its periphery. Each bucket consists of two
symmetrical halves having shape of semi-ellipsoidal
cup. These symmetrical parts are divided by a sharp
edged ridge called splitter. Water, at high head, flows
through the penstock and at the end of penstock, one
or more nozzles are fitted to convert all the available
energy of water into kinetic energy. The water comes
out of the nozzle as jet and impinges on the buckets,
causing it to revolve. The impact of water jet
produces force on bucket causing wheel to rotate. The
jet of water splits equally by splitter and flows round
the inner bucket surface and leaves at the outer edge
of buckets. The buckets have special shape of double
hemispherical cups. The rear of the bucket is designed
such that the water leaving the bucket should not
interfere with the passage of water to the preceding
bucket.
Model testing is the most common method
for assessing the performance of any turbine. But this
is time consuming, costly and does not provide
detailed
flow
information.
The
improved
computational facility and advanced numerical
techniques made possible detailed flow analysis in
given flow domain for design optimization of
machines.
In the last few decades, a lot of work has
been done for optimisation of jet quality and bucket
shape of impulse turbine. Many authors have worked
for finding out most efficient shape of nozzle. Still
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performance prediction of Pelton turbine for different
shapes of jets is a thrust area for research because of
multiphase and transient flow.
Kotousov (2005) experimentally and Gupta
et al. (2009) numerically found out that circular
conical nozzles are most efficient ones. Perrig at al.
(2006), Zoppe et al. (2006), Jost et al. (2010),
Dynampally and Rao (2012) and Desai et al. (2012)
have performed flow analysis of rotating Pelton
turbine considering jet of circular cross section using
various commercially available CFD codes. Zhang
and Casey (2007) and Patel et al. (2010) have
experimentally found out that for circular jet, jet core
shifts from the axis of nozzle due to secondary flows
generated by the bends or bifurcations present in the
distributor of Pelton turbine system. With the help of
CFD Peron et al (2008) improved the performance of
Pelton turbine for two rehabilitation projects in
Bordogna and Switzerland for circular jets. Gupta and
Prasad (2012) analysed force experienced by the jet
of different shapes on static bucket.
Fig 1:Parts of Pelton Turbine
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2. Vishal Gupta et al Int. Journal of Engineering Research and Applications
ISSN : 2248-9622, Vol. 4, Issue 1( Version 1), January 2014, pp. 318-323
www.ijera.com
In the present paper, numerical flow
simulation of a six jet Pelton turbine shown in fig.1
for different shapes of jets with same cross sectional
area has been carried out to access its performance at
best efficiency point (BEP) by using commercial CFD
code.
II.
GEOMETRIC MODELING
In the present work, for the study of jet
shape, the domain from exit of nozzle to runner was
created. Due to limitation of computational power,
only three symmetrical half jets with 10 symmetrical
half buckets were created. The geometry of runner
and stator is done separately. The stator is modeled
for circular, triangular, square, ellipse jet inlet shown
in fig 2 to fig 5. The symmetrical half of rotor is
having 10 buckets as shown in fig 6. The modeling
has been done in ICEM CFD.
Fig. 4: Stator with square inlet
Fig. 2: Stator with circular inlet
Fig. 5: Stator with elliptical inlet
Fig. 6: Rotor domain
Fig. 3: Stator with triangular inlet
III.
MESH GENERATION
The complete flow regime is discretised into
grid having tetrahedral elements for flow space and
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3. Vishal Gupta et al Int. Journal of Engineering Research and Applications
ISSN : 2248-9622, Vol. 4, Issue 1( Version 1), January 2014, pp. 318-323
triangular elements for surfaces. The mesh of stator
domain with square inlet has been shown in fig.7.
Prismatic elements have been applied near jet wall
and bucket surface for better resolution of boundary
layer.
V.
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FORMULAE USED
The jet after striking the buckets with force,
gets deflected towards the outlet of the buckets. The
jet exerts torque on the buckets and thus the runner
rotates. The following formulae are used for
computation of parameters of turbine:
Theoretical power input:
PI g Q H
(1)
Power output:
PO
2 N T
60
(2)
Hydraulic efficiency:
Fig. 7: Meshing of stator domain with square inlet
IV.
INPUT DATA AND BOUNDARY
CONDITIONS
Stator domain is kept stationary while the
rotor domain is specified rotational speed of 820 rpm.
The SST turbulent model given by Menter with
automatic wall function was used as SST model is
able to capture the flow in the region of higher shear
stresses by solving a turbulence based model (k–ω) at
the wall and k-ε in the region of bulk flow.
In transient analysis, the time step plays a
vital role. For larger time steps, the efficiency
decreases and for smaller time steps, efficiency can be
predicted well but the computational time increases
drastically. So due to the limitation of computational
power, time step corresponding to 1° (2.032×10 -4sec)
runner rotation was considered.
For numerically obtaining solution of a
problem, boundary conditions at inlet and outlet are
required to be defined and the solution of the problem
depends on values given at boundary conditions. In
present case, air and water with reference pressure of
1 atmospheric pressure are taken. Transient flow
simulation with time step corresponding to l° runner
rotation has been taken.
Jet inlet is defined as inlet with water
velocity of 30.7 m/s normal to surface. Jet symmetry,
stator symmetry, rotor symmetry have been defined
as symmetric type boundary conditions. Periodicity
has been applied at both symmetric ends of stator and
rotor. As the flow around impulse turbine is at
atmospheric pressure, opening type boundary
conditions are applied at stator side opening, stator
top opening, rotor side opening and rotor mid opening
with relative pressure of 0 atmospheric. Transient
rotor-stator interface is set between both the domains.
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h
Po
PI
(3)
Time step corresponding to 1° runner rotation:
t
60
360 N
VI.
(4)
MESH INDEPENDENCY TEST
In numerical simulation, size of mesh and its
quality affects the accuracy of results. The mesh
independency test was carried out only for circular
shape of jet. Same mesh size was given for other
stators. The quality of the mesh was checked to be
within the recommended values of ANSYS CFX. It
was found that result becomes independent of stator
mesh at 456213 nodes and for rotor, the torque
becomes independent of mesh size after 1537618
nodes.
VII.
RESULTS AND DISCUSSIONS
The flow simulation has been carried out at
best efficiency point keeping cross sectional area of
jets constant for each case. The numerical results for
efficiency are validated with experimental results for
circular jet at best efficiency point. The efficiency
obtained from numerical simulation for circular jet is
88.03% which is close to experimental value of
91.5%. The results are analysed for water volume
fraction iso-surfaces, pressure distribution within the
flow domains.
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4. Vishal Gupta et al Int. Journal of Engineering Research and Applications
ISSN : 2248-9622, Vol. 4, Issue 1( Version 1), January 2014, pp. 318-323
www.ijera.com
Fig 11: Water sheet for elliptical jet
Fig 8: Water sheet for circular jet
Spreading of water is more uniform for
circular jet as seen in fig 8 and for triangular and
square shaped jets in fig 9 and fig 10, water jet is
unable to pass through the cut out which causes early
interaction of water with bucket. In case of elliptical
jet also, water spreads large over full surface of
bucket as shown in fig 11.
Fig 9: Water sheet for triangular jet
Fig.12: Water volume fraction contour at mid span of
bucket for various jet shapes at BEP
Fig 10: Water sheet for square jet
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It is observed from fig 12 that for circular
and elliptical jets, buckets get fully emptied before
reaching in front of next jet. But in case of triangular
and square jets, the buckets are not completely
emptied before reaching the next jet and this may
create hindrance in the path of coming jet of water.
This will lead in poor performance of turbine runner.
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5. Vishal Gupta et al Int. Journal of Engineering Research and Applications
ISSN : 2248-9622, Vol. 4, Issue 1( Version 1), January 2014, pp. 318-323
www.ijera.com
Fig 16: Pressure contour on buckets for elliptical jet
Fig 13: Pressure contour on buckets for circular jet
From fig 13 to fig 16 it is observed that the
highest pressure is observed at the deepest zone of the
buckets. Splitter and cut out also experience higher
pressure as compared to other parts of buckets in all
cases.
Fig 14: Pressure contour on buckets for triangular jet
Fig 17: Variation of torque on buckets with angle of
rotation
Fig 15: Pressure contour on buckets for square jet
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It is seen from fig 17 that torque increase is
gradual and rate of increase is same for all jet shapes
up to 40°. And again after 80° rotation, the value of
torque becomes nearly constant for all jet shapes.
Torque value increases when the buckets are in front
of the jets and decreases as the distance between jets
and buckets increases. Average value of torque is
observed to be maximum for circular jet and
minimum for elliptical jet. This is due to the less
surface area of circular jet in contact with air. The
values of hydraulic efficiency from numerical
simulation for different jet shapes are given in table 1.
It is seen that highest efficiency is achieved for
circular jet and minimum for elliptical jet shape.
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6. Vishal Gupta et al Int. Journal of Engineering Research and Applications
ISSN : 2248-9622, Vol. 4, Issue 1( Version 1), January 2014, pp. 318-323
Table 1: Variation in hydraulic efficiency for different
jet shapes
Jet
Circula Triangul Squar Elliptic
Shape
r
ar
e
al
77.80
84.72
76.56
Numeric 88.03
al
Efficienc
y
[6]
[7]
VIII.
CONCLUSION
It is found from numerical simulation of
Pelton turbine at best efficiency point for different
shapes that the circular jet are the most efficient
giving highest efficiency. The spreading of water over
the bucket is found to be more uniform for circular
jet. The sharp edges of the jet other than circular
shape give poor efficiency of the turbine because of
uneven distribution of water on bucket surface. Very
fine mesh is needed for performance prediction of
Pelton turbines which requires very high
computational power.
NOMENCLATURE
PI- power input (W)
ρ- density of working fluid
Q- discharge (m3/s)
H- head (m)
g- acceleration due to gravity (9.8 m/s2)
ηh- hydraulic Efficiency (%)
N- rotational speed of rotor (rpm)
T- torque at rotor (N-m)
PO- numerical Power Output (W)
ηN - numerical Efficiency (%)
[8]
[9]
[10]
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Hydraulic
Efficiency
Measurements
(IGHEM-2008), 3-6 September, 2008,
Milano.
K. Patel, B. Patel, M. Yadav and T. Foggia,
Development of Pelton turbine using
numerical simulation, transaction of IOP
Science, 25th IAHR Symposium on
Hydraulic Machinery and Systems, 2010
D. Jost, P. Meznar, A. Lipej, Numerical
prediction of Pelton turbine efficiency,
transaction of IOP Science, 25th IAHR
Symposium on Hydraulic Machinery and
Systems, 2010.
V. Gupta and V. Prasad, Numerical
Investigations for Jet Flow Characteristics on
Pelton Turbine Bucket, International Journal
of Emerging Technology and Advanced
Engineering, Volume 2, Issue 7, July 2012,
pp 364-370.
P. Dynampally and V.S. Rao, CFD Analysis
of Pelton Turbine, Proceedings of Thirty
Ninth National Conference on Fluid
Mechanics and Fluid Power, SVNIT, Surat,
Gujarat, India, 2012, FMFP2012- 58.
J.D. Desai,., V.A. Soni,., V.K. Chauhan,.,
S.S. Charania,. and K.C. Patel, Evaluation of
Twin Jet Pelton Turbine Using CFD,
Proceedings of Thirty Ninth National
Conference on Fluid Mechanics and Fluid
Power, SVNIT, Surat, Gujarat, India, 2012,
FMFP2012- 194.
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L.S. Kotousov, Measurement of the Water
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Perrig, F. Avellan, J.L. Kueny and M.
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Zoppe, C. Pellone, T. Maitre and P. Leroy,
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Bucket, Transaction of ASME, Vol. 128,
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