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Arpita-CANCAM

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Indian Institute of Technology, Madras
Indian Institute of Technology, Madras

This document summarizes a numerical investigation of a jet pump with twisted tapes. A 3D numerical model was developed using ANSYS Fluent to simulate flow through a jet pump with variations in nozzle profile and the addition of single or double twisted tapes in the primary nozzle. Results showed that a double twisted tape increased jet pump efficiency the most, by around 10%, compared to a nozzle without tape. Higher velocities, turbulent kinetic energy, and vorticity were observed with twisted tapes, enhancing entrainment of the secondary flow and improving performance.

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Proceedings of the 25th CANCAM London, Ontario, Canada, May 31 – June 4, 2014 NUMERICAL INVESTIGATION OF JET PUMP WITH TWISTED TAPES Arpita Srivastava Department of Mechanical Engineering Indian Institute of Technology Chennai, Tamil Nadu, India arpita.sri.lko@gmail.com Shaligram Tiwari Department of Mechanical Engineering Indian Institute of Technology Chennai, Tamil Nadu, India shaligram@gmail.com Mani Annamalai Department of Mechanical Engineering Indian Institute of Technology Chennai, Tamil Nadu, India mania@iitm.ac.in ABSTRACT Jet pump is used to transfer momentum from a high velocity primary stream to a secondary stream that gets entrained. It is packaged with the advantage of geometrical simplicity without any moving parts. It comprises mainly of a nozzle, mixing chamber and diffuser. It is used in numerous applications, one such being desalination systems, where it helps in creating vacuum inside the flash chamber without employing conventional oil vacuum pump. Aim of the present study is to carry out three-dimensional numerical investigations of two phase flow jet pump in presence of twisted tapes under optimized conditions of the parameters such as upstream and downstream pressures, primary jet mass flow rate, entrained secondary stream mass flow rate, geometry of the ejector, etc. Investigations of swirling turbulent jet flows are carried out using suitable turbulent model in ANSYS FLUENT. This investigation helps in predicting the flow behavior at the exit of nozzle with respect to different nozzle profiles causing dispersion in jet and also due to introduction of the swirl. At first, the three- dimensional numerical computations have been carried out to validate the existing literature without introduction of swirl in primary stream. Further investigations are carried out to identify the effect of tape with respect to the case without tape. Water and air have been used as fluids in the primary and secondary streams respectively. Nozzle profiles selected is conical. The mean diameter of nozzles are kept to be 4mm and 6mm. Results in present study suggest that the momentum exchange achieved by the swirl causes significant enhancement efficiency of the jet pump. KEYWORDS: Jet pump, nozzle profile, two phase flow, twisted tape. INTRODUCTION The ejectors employed in jet pumps causes a complex flow physics and hence it is preferably modeled in 3D incorporating CFD which gives us the advantage over neglecting 1D assumptions and predicted very near to actual situation. Several investigations have been reported for enhancing its efficiency. Many researchers carried out valuable experiments to determine the conditions at which improvements can be achieved. Pfliedderer [1] proposed that the pressure ratio and air flow rate are independent of each other. Martinelli et al. [2] reported that increase in air flow rate at secondary inlet with an increase in flow rate of water at the primary side is due to increased pressure at primary motive fluid. Many researchers have performed studies on multi hole nozzle. Decay of primary jet flow as well as length of potential core depends on how the phenomenon of momentum exchange occurs between two fluids stream in mixing zone near to primary nozzle exit. Sharma [9] in his work experimentally verified that, for lower area ratio, nozzles having elliptical profile are capable of producing higher efficiency then nozzles with circular or conical profile. He experimented with different area ratio of nozzle. The geometrical design for the present study is taken from Sharma’s experiment. Hansen and Kinnavy [5] performed experiments on ejectors keeping different area ratio and then studied different parametric effect. It was concluded that area ratio has major role to play in ejector efficiency than any other parameter. Abdus Samad [10] investigated the influence of the introduction of swirl low performance of an ejector and concluded that it enhance the jet breakup resulting in higher suction rates at different optimized swirl angles. GOVERNING EQUATION AND NUMERICAL TREATMENT Governing equations solved are the mass and momentum conservation equations. For steady state, incompressible flow with constant viscosity, these equations can be expressed as (1) (2) In these equations, ui refers to the mean velocity along xaxis, P the static pressure and the kinematic viscosity of fluid. CFD helps to formulate the required governing equations involved in fluid flow into numbers such as to get a final desired description of the complete flow field under observation numerically. The observation and results obtained out of CFD are near to actual flow and it has been proved in large number of applications. Riffat et al. [6] have employed CFD tools and application to determine the optimum design of the ejector. Not only this, he examined the various performance characteristic obtained during

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simulation to compare using primary nozzles of various geometries with different types of working fluid. Later, the performance of ejector in a compressible flow was studied by varying the nozzle position with respect to mixing chamber by Riffat and Omer [7] for a refrigeration system using CFD model. Gas powered Jet pump performance also depends on its diffuser design which was analyzed by Neve [11] numerically using CFD tools. Ouzzane and Aidoun [12], investigated on ejector and put forward one-dimensional flow model involved in their studies. Bartosiewicz [8] performed numerical analysis on the ejector with working fluid as air, using CFD software FLUENT. They validated the existing CFD results obtained with the experimental investigations made. Further these studies were extended to optimize the turbulent model to capture more physical realistic situation occurring in flow field. Many studies has proposed that introduction of swirl in the primary jet may increase the overall efficiency of jet pump by improving the entrainment of secondary fluid. STATEMENT OF THE PROBLEM The present numerical validation studies have conducted with the results of Sharma’s experimental work [9]. Problem is being defined numerically considering it to be a steady flow, incompressible situation. The pressure-based steady flow Navier-Stokes solution’s algorithm has been followed to reach out the solution. The efficiency of the jet pump was calculated by considering upstream pressure, pressure at diffuser, secondary and flow ratio. (3) Figure1: Schematic cross section of jet pump It excludes the effect of pipes and connecting elements used in the experimental setup. The steady state of the jet pump is modeled maximum evacuation of air in the vacuum chamber is achieved. The 3-D geometry is simulated to ensure that maximum physical turbulent flow field can be captured and studied. The major details of the dimensions of the ejector employed are given in Table 1. The profile of the nozzle is changed keeping other geometrical parameters as the same. For validation, nozzle of circular, elliptical and conical profiles, with 4mm nozzle diameter, are compared and found that elliptical nozzle has better efficiency than others. Table 1.Design parameters of nozzle Notation Name Dimension Do Nozzle diameter 4 mm and 6mm Dsuc Suction chamber diameter 21mm Dmt Mixing tube diameter 10mm Dst Inlet diameter of supply tube 21mm Lmt Length of the mixing tube 265mm S Distance between nozzle and mixing tube 31mm Ld Length of the diffuser 135mm Dd Diameter of the diffuser at outlet 21mm  Diffuser semi cone angle 2°30’ This geometry is termed as the ‘base geometry’ in this study as shown in figure 1. For the studies with twisted tape in conical nozzle, the diameter of the mixing tube (Dmt) and the diffuser element downstream of the mixing tube were kept constant. For the present study CFD software ANSYS Fluent is used which incorporates a finite volume code for the preset simulations. This code solves the discretized equations in a segregated manner, with SIMPLE algorithm. The first-order upwind scheme is taken for momentum, volume fraction, turbulent Kinetic energy and turbulent dissipation rate discretisation. The solutions were assumed to have converged for the residual level of 10-4 for continuity, x- velocity, and y velocity and 10-6 for k -epsilon. Creation of the geometries was carried out in Solid works and then imported to ANSYS Workbench for meshing of the computational domains. To ensure better insight view of fluid flow and mixing grid independent study was carried out for ejector with conical nozzle incorporating twisted tape. For performing the grid study, geometries with mesh size of 167231cells, 257111 cells, 430017 cells 707808 cells, 864906 cells, 1072648 cells and 1755598 cells were numerically analyzed. Minimum orthogonal quality was kept at 0.5.The grid size was optimized by head difference. It was observed that for the geometries with higher mesh size, variation in head difference was almost negligible. Since after 7.8lakhs grid size there was no such significant difference in pressure contours this was fixed as grid size for all the further simulations which include swirl generators also. Boundary conditions used for each simulation are known static absolute pressure. Turbulent intensity was selected 5 % and respective hydraulic diameters were used at each of the flow boundaries. DESCRIPTION To get the swirling flows single and double twisted tapes, as shown in figures 2 to 3, has been used in figure 4. The twisted-tapes are characterized by the twist ratio defined by the ratio between the tape turn length of 180º along its axis and the tube diameter. The length of twisted tape is 40mm and width is 18mm.Thickness of the tape used are 1mm and Mixing Chamber Secondary Inlet Primary nozzle Diffuser

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1.5mm Single Twisted tapes, used in current study, are 90 degree tape turn with twist ratio 1.11. Similarly double twisted tapes are also used in primary flow such as two tapes right angled to each other are twisted at 90 degree. Figure 2: Single twisted tape Figure 3: Double Twisted Tape Figure 4: Pictorial representation of double twisted tape incorporated in primary nozzle RESULTS AND DISCUSSION On performing numerical studies, the ejector incorporating double twisted tape is found to be highly efficient comparatively to other ejector combination. It is also found that single twisted tape has the lesser efficiency than double twisted tape but better than without tape. The Table 2.shows the comparative parametric studies carried out along with performance obtained. The twisted tape studies are performed for higher area ratio in conical nozzle as for higher diameter of nozzles are found more efficient than smoother profiled nozzle by Sharma [9]. The velocity, turbulent kinetic energy and vorticity magnitude graphs have been plotted against the length of the ejector, as shown in figures 5 to 7.The velocity contours in figure 8 shows that the maximum velocity was attained in the conical nozzle with double twisted tape having thickness 1.5mm. Efficiency of this arrangement is increased by 10% when compared with nozzle, without any tape. Table 2: Comparison of various operating parameters and performance Parameters Without tape Single twisted tape Double twisted Tape 1mm 1.5mm 1.5mm 1mm Water flowrate Qw(lps) 1 1 1 1 1 Air Flowrate Qa(lps) 1.6 1.63 1.63 1.8 1.72 Flow Ratio 1.7 1.63 1.63 1.8 1.72 Upstream Pressure(Bar absolute) 8.9 8.9 8.9 8.9 8.9 Downstream Pressure(Bar Absolute) 1.81 1.81 1.81 1.81 1.81 Suction Pressure(Bar Absolute) 1.01306 1.01311 1.01311 1.01306 1.01306 Efficiency ɳ (in %) 18.4 18.4 18.4 20.4 19.5 Position (mm) Figure 5: Velocity profiles for jet pump with different twisted tape CONCLUSIONS It has been observed that there is a change in flow behavior after the nozzle when twisted tapes are inserted in the upstream primary fluid and more pressure drops after the nozzle is observed due to high vorticity magnitude. This enhances the volume flow rate of the secondary air which ultimately results in better entrainment. Double Twisted Tape Nozzle exit Secondary Inlet Velocity(m/s) Primary Inlet

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Position(mm) Figure 6: Turbulent kinetic energy profiles for jet pump with different twisted tape Position (mm) Figure 7: Vorticity magnitude profiles for jet pump with different twisted tape Figure 8: Velocity contours at the mid plane for different Jet pumps REFERENCES 1. Pfleiderer, C., “Experiments on jet pump for its performance”, C. Zeit, VDI, 58, 965 &1011. 2. Martinelli, R.C., Boelter, L. M. K., Morrin, E. H., “Theoretical and experimental analysis of ejectors Trans. ASME, 66, pp. 139-151. 3. Senthil Kumar, R., Mani, A., Kumaraswamy, S. 2004, “Selection of Pumps for Vacuum Desalination System Utilizing Ocean Thermal Energy, 31st National Conference on Fluid Mechanics and Fluid Power, Vol. 1, pp. 409–416. 4. Senthil Kumar, R., Mani,A., Kumaraswamy, S., 2007, “Experimental Investigation on Two-Phase Jet Pump used in Desalination System ” , Desalination, 204, pp. 437-447. 5. Hansen, A. G., and Kinnavy, R. 1965, “The design of water jet pumps part I – experimental determination of optimum design parameters”. ASME Paper 65-WA/FE-31. 6. Riffat, S. B., Gan, G., and Smith, S., 1996, Computational fluid dynamics applied to ejector heat pumps, Journal of Applied Thermal Engineering, 16, 291-297. 7. Riffat, S. B., and Omer, S. A. 2001, CFD modeling and experimental investigations of an ejector refrigeration system, Int. Journal on Energy Research, 25, 115-128. 8. Bartosiewicz, Y., Aidoun, Z., Mercadier, Y., 2006, “Numerical assessment of ejector operation for refrigeration applications based on CFD”, Applied Thermal Engineering, n 26, pp.604–612. 9. Sharma, V. Kumar., Kumaraswamy, S., Mani, A. 2012, “Effect of Various Nozzle Profiles on Performance of a Two Phase Flow Jet Pump”. Int. Journal of Mechanical and Aerospace Eng,6, p.136- 142. 10. Samad, A., Omar, R., Hewakandamby, B., Lowndes I., and Short, G. 2012, “Swirl Induced Flow Through a Venturi-Ejector,” ASME 2012 Fluids Engineering Division Summer Meeting (FEDSM2012), Puerto Rico, USA. 11. Neve, R. S. 1993, “Computational fluid dynamics analysis of diffuser performance in gas-powered jet pumps”, Int. Journal on Heat and Fluid flow, 14, 401-407. 12. Ouzzane, M., and Aidoun, Z. 2003, Model development and numerical procedure for detailed ejector analysis and design, Journal of Applied Engineering, 23, 2337-2351. Turbulentkineticenergy (m2 /s2 ) Vorticity(1/s) Velocity, m/s

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Arpita-CANCAM

  • 1. Proceedings of the 25th CANCAM London, Ontario, Canada, May 31 – June 4, 2014 NUMERICAL INVESTIGATION OF JET PUMP WITH TWISTED TAPES Arpita Srivastava Department of Mechanical Engineering Indian Institute of Technology Chennai, Tamil Nadu, India arpita.sri.lko@gmail.com Shaligram Tiwari Department of Mechanical Engineering Indian Institute of Technology Chennai, Tamil Nadu, India shaligram@gmail.com Mani Annamalai Department of Mechanical Engineering Indian Institute of Technology Chennai, Tamil Nadu, India mania@iitm.ac.in ABSTRACT Jet pump is used to transfer momentum from a high velocity primary stream to a secondary stream that gets entrained. It is packaged with the advantage of geometrical simplicity without any moving parts. It comprises mainly of a nozzle, mixing chamber and diffuser. It is used in numerous applications, one such being desalination systems, where it helps in creating vacuum inside the flash chamber without employing conventional oil vacuum pump. Aim of the present study is to carry out three-dimensional numerical investigations of two phase flow jet pump in presence of twisted tapes under optimized conditions of the parameters such as upstream and downstream pressures, primary jet mass flow rate, entrained secondary stream mass flow rate, geometry of the ejector, etc. Investigations of swirling turbulent jet flows are carried out using suitable turbulent model in ANSYS FLUENT. This investigation helps in predicting the flow behavior at the exit of nozzle with respect to different nozzle profiles causing dispersion in jet and also due to introduction of the swirl. At first, the three- dimensional numerical computations have been carried out to validate the existing literature without introduction of swirl in primary stream. Further investigations are carried out to identify the effect of tape with respect to the case without tape. Water and air have been used as fluids in the primary and secondary streams respectively. Nozzle profiles selected is conical. The mean diameter of nozzles are kept to be 4mm and 6mm. Results in present study suggest that the momentum exchange achieved by the swirl causes significant enhancement efficiency of the jet pump. KEYWORDS: Jet pump, nozzle profile, two phase flow, twisted tape. INTRODUCTION The ejectors employed in jet pumps causes a complex flow physics and hence it is preferably modeled in 3D incorporating CFD which gives us the advantage over neglecting 1D assumptions and predicted very near to actual situation. Several investigations have been reported for enhancing its efficiency. Many researchers carried out valuable experiments to determine the conditions at which improvements can be achieved. Pfliedderer [1] proposed that the pressure ratio and air flow rate are independent of each other. Martinelli et al. [2] reported that increase in air flow rate at secondary inlet with an increase in flow rate of water at the primary side is due to increased pressure at primary motive fluid. Many researchers have performed studies on multi hole nozzle. Decay of primary jet flow as well as length of potential core depends on how the phenomenon of momentum exchange occurs between two fluids stream in mixing zone near to primary nozzle exit. Sharma [9] in his work experimentally verified that, for lower area ratio, nozzles having elliptical profile are capable of producing higher efficiency then nozzles with circular or conical profile. He experimented with different area ratio of nozzle. The geometrical design for the present study is taken from Sharma’s experiment. Hansen and Kinnavy [5] performed experiments on ejectors keeping different area ratio and then studied different parametric effect. It was concluded that area ratio has major role to play in ejector efficiency than any other parameter. Abdus Samad [10] investigated the influence of the introduction of swirl low performance of an ejector and concluded that it enhance the jet breakup resulting in higher suction rates at different optimized swirl angles. GOVERNING EQUATION AND NUMERICAL TREATMENT Governing equations solved are the mass and momentum conservation equations. For steady state, incompressible flow with constant viscosity, these equations can be expressed as (1) (2) In these equations, ui refers to the mean velocity along xaxis, P the static pressure and the kinematic viscosity of fluid. CFD helps to formulate the required governing equations involved in fluid flow into numbers such as to get a final desired description of the complete flow field under observation numerically. The observation and results obtained out of CFD are near to actual flow and it has been proved in large number of applications. Riffat et al. [6] have employed CFD tools and application to determine the optimum design of the ejector. Not only this, he examined the various performance characteristic obtained during
  • 2. simulation to compare using primary nozzles of various geometries with different types of working fluid. Later, the performance of ejector in a compressible flow was studied by varying the nozzle position with respect to mixing chamber by Riffat and Omer [7] for a refrigeration system using CFD model. Gas powered Jet pump performance also depends on its diffuser design which was analyzed by Neve [11] numerically using CFD tools. Ouzzane and Aidoun [12], investigated on ejector and put forward one-dimensional flow model involved in their studies. Bartosiewicz [8] performed numerical analysis on the ejector with working fluid as air, using CFD software FLUENT. They validated the existing CFD results obtained with the experimental investigations made. Further these studies were extended to optimize the turbulent model to capture more physical realistic situation occurring in flow field. Many studies has proposed that introduction of swirl in the primary jet may increase the overall efficiency of jet pump by improving the entrainment of secondary fluid. STATEMENT OF THE PROBLEM The present numerical validation studies have conducted with the results of Sharma’s experimental work [9]. Problem is being defined numerically considering it to be a steady flow, incompressible situation. The pressure-based steady flow Navier-Stokes solution’s algorithm has been followed to reach out the solution. The efficiency of the jet pump was calculated by considering upstream pressure, pressure at diffuser, secondary and flow ratio. (3) Figure1: Schematic cross section of jet pump It excludes the effect of pipes and connecting elements used in the experimental setup. The steady state of the jet pump is modeled maximum evacuation of air in the vacuum chamber is achieved. The 3-D geometry is simulated to ensure that maximum physical turbulent flow field can be captured and studied. The major details of the dimensions of the ejector employed are given in Table 1. The profile of the nozzle is changed keeping other geometrical parameters as the same. For validation, nozzle of circular, elliptical and conical profiles, with 4mm nozzle diameter, are compared and found that elliptical nozzle has better efficiency than others. Table 1.Design parameters of nozzle Notation Name Dimension Do Nozzle diameter 4 mm and 6mm Dsuc Suction chamber diameter 21mm Dmt Mixing tube diameter 10mm Dst Inlet diameter of supply tube 21mm Lmt Length of the mixing tube 265mm S Distance between nozzle and mixing tube 31mm Ld Length of the diffuser 135mm Dd Diameter of the diffuser at outlet 21mm  Diffuser semi cone angle 2°30’ This geometry is termed as the ‘base geometry’ in this study as shown in figure 1. For the studies with twisted tape in conical nozzle, the diameter of the mixing tube (Dmt) and the diffuser element downstream of the mixing tube were kept constant. For the present study CFD software ANSYS Fluent is used which incorporates a finite volume code for the preset simulations. This code solves the discretized equations in a segregated manner, with SIMPLE algorithm. The first-order upwind scheme is taken for momentum, volume fraction, turbulent Kinetic energy and turbulent dissipation rate discretisation. The solutions were assumed to have converged for the residual level of 10-4 for continuity, x- velocity, and y velocity and 10-6 for k -epsilon. Creation of the geometries was carried out in Solid works and then imported to ANSYS Workbench for meshing of the computational domains. To ensure better insight view of fluid flow and mixing grid independent study was carried out for ejector with conical nozzle incorporating twisted tape. For performing the grid study, geometries with mesh size of 167231cells, 257111 cells, 430017 cells 707808 cells, 864906 cells, 1072648 cells and 1755598 cells were numerically analyzed. Minimum orthogonal quality was kept at 0.5.The grid size was optimized by head difference. It was observed that for the geometries with higher mesh size, variation in head difference was almost negligible. Since after 7.8lakhs grid size there was no such significant difference in pressure contours this was fixed as grid size for all the further simulations which include swirl generators also. Boundary conditions used for each simulation are known static absolute pressure. Turbulent intensity was selected 5 % and respective hydraulic diameters were used at each of the flow boundaries. DESCRIPTION To get the swirling flows single and double twisted tapes, as shown in figures 2 to 3, has been used in figure 4. The twisted-tapes are characterized by the twist ratio defined by the ratio between the tape turn length of 180º along its axis and the tube diameter. The length of twisted tape is 40mm and width is 18mm.Thickness of the tape used are 1mm and Mixing Chamber Secondary Inlet Primary nozzle Diffuser
  • 3. 1.5mm Single Twisted tapes, used in current study, are 90 degree tape turn with twist ratio 1.11. Similarly double twisted tapes are also used in primary flow such as two tapes right angled to each other are twisted at 90 degree. Figure 2: Single twisted tape Figure 3: Double Twisted Tape Figure 4: Pictorial representation of double twisted tape incorporated in primary nozzle RESULTS AND DISCUSSION On performing numerical studies, the ejector incorporating double twisted tape is found to be highly efficient comparatively to other ejector combination. It is also found that single twisted tape has the lesser efficiency than double twisted tape but better than without tape. The Table 2.shows the comparative parametric studies carried out along with performance obtained. The twisted tape studies are performed for higher area ratio in conical nozzle as for higher diameter of nozzles are found more efficient than smoother profiled nozzle by Sharma [9]. The velocity, turbulent kinetic energy and vorticity magnitude graphs have been plotted against the length of the ejector, as shown in figures 5 to 7.The velocity contours in figure 8 shows that the maximum velocity was attained in the conical nozzle with double twisted tape having thickness 1.5mm. Efficiency of this arrangement is increased by 10% when compared with nozzle, without any tape. Table 2: Comparison of various operating parameters and performance Parameters Without tape Single twisted tape Double twisted Tape 1mm 1.5mm 1.5mm 1mm Water flowrate Qw(lps) 1 1 1 1 1 Air Flowrate Qa(lps) 1.6 1.63 1.63 1.8 1.72 Flow Ratio 1.7 1.63 1.63 1.8 1.72 Upstream Pressure(Bar absolute) 8.9 8.9 8.9 8.9 8.9 Downstream Pressure(Bar Absolute) 1.81 1.81 1.81 1.81 1.81 Suction Pressure(Bar Absolute) 1.01306 1.01311 1.01311 1.01306 1.01306 Efficiency ɳ (in %) 18.4 18.4 18.4 20.4 19.5 Position (mm) Figure 5: Velocity profiles for jet pump with different twisted tape CONCLUSIONS It has been observed that there is a change in flow behavior after the nozzle when twisted tapes are inserted in the upstream primary fluid and more pressure drops after the nozzle is observed due to high vorticity magnitude. This enhances the volume flow rate of the secondary air which ultimately results in better entrainment. Double Twisted Tape Nozzle exit Secondary Inlet Velocity(m/s) Primary Inlet
  • 4. Position(mm) Figure 6: Turbulent kinetic energy profiles for jet pump with different twisted tape Position (mm) Figure 7: Vorticity magnitude profiles for jet pump with different twisted tape Figure 8: Velocity contours at the mid plane for different Jet pumps REFERENCES 1. Pfleiderer, C., “Experiments on jet pump for its performance”, C. Zeit, VDI, 58, 965 &1011. 2. Martinelli, R.C., Boelter, L. M. K., Morrin, E. H., “Theoretical and experimental analysis of ejectors Trans. ASME, 66, pp. 139-151. 3. Senthil Kumar, R., Mani, A., Kumaraswamy, S. 2004, “Selection of Pumps for Vacuum Desalination System Utilizing Ocean Thermal Energy, 31st National Conference on Fluid Mechanics and Fluid Power, Vol. 1, pp. 409–416. 4. Senthil Kumar, R., Mani,A., Kumaraswamy, S., 2007, “Experimental Investigation on Two-Phase Jet Pump used in Desalination System ” , Desalination, 204, pp. 437-447. 5. Hansen, A. G., and Kinnavy, R. 1965, “The design of water jet pumps part I – experimental determination of optimum design parameters”. ASME Paper 65-WA/FE-31. 6. Riffat, S. B., Gan, G., and Smith, S., 1996, Computational fluid dynamics applied to ejector heat pumps, Journal of Applied Thermal Engineering, 16, 291-297. 7. Riffat, S. B., and Omer, S. A. 2001, CFD modeling and experimental investigations of an ejector refrigeration system, Int. Journal on Energy Research, 25, 115-128. 8. Bartosiewicz, Y., Aidoun, Z., Mercadier, Y., 2006, “Numerical assessment of ejector operation for refrigeration applications based on CFD”, Applied Thermal Engineering, n 26, pp.604–612. 9. Sharma, V. Kumar., Kumaraswamy, S., Mani, A. 2012, “Effect of Various Nozzle Profiles on Performance of a Two Phase Flow Jet Pump”. Int. Journal of Mechanical and Aerospace Eng,6, p.136- 142. 10. Samad, A., Omar, R., Hewakandamby, B., Lowndes I., and Short, G. 2012, “Swirl Induced Flow Through a Venturi-Ejector,” ASME 2012 Fluids Engineering Division Summer Meeting (FEDSM2012), Puerto Rico, USA. 11. Neve, R. S. 1993, “Computational fluid dynamics analysis of diffuser performance in gas-powered jet pumps”, Int. Journal on Heat and Fluid flow, 14, 401-407. 12. Ouzzane, M., and Aidoun, Z. 2003, Model development and numerical procedure for detailed ejector analysis and design, Journal of Applied Engineering, 23, 2337-2351. Turbulentkineticenergy (m2 /s2 ) Vorticity(1/s) Velocity, m/s