Performance Evaluation of Water Jet Pump for Nozzle to ...

1 International Journal of Mechanical & Mechatronics Engineering IJMME-IJENS Vol:14 No:03 45. Performance Evaluation of Water Jet Pump for Nozzle to Throat Area Ratios on Suction Lift Md. Mizanur Rahman1, Md. Assad-Uz-zaman2 and Mohammad Mashud3.. Abstract The experiment was about to study of Water jet advantage of locating all the moving parts of the pump on the pumps with different diameters and Nozzle -to-throat area ratios. surface with only the venturi section underground. Most experimental studies on Water jet pumps mainly carried out Most experimental study was conducted in this field to get to assess the maximum efficiency. But maximum efficiency the maximum efficiency but very few were done on suction occurs when the suction lift is relatively small for a given head loss through the pump, which implies, when the suction flow rate lift.

2 In many cases suction lift is more important than is maximum. However, suction lift is inversely proportional to maximum efficiency. To do so, an afford was made to get the flow rate. But in the field of application there are many cases effect of nominal diameter and Nozzle to throat area ratio on (such as drainage, dredging, well-pumping and other systems) suction lift of Water jet pumps. where suction lift is more important factor than any other for Water jet pumps, which gives importance to the assessment of depending factor of suction lift of Water jet pumps. Six different II. WORKING PRINCIPLE. jet pumps of two different nominal diameter each of three A centrifugal pump delivered Water from a feed tank to different Nozzle to throat area ratio were made to carry out this the jet pump. The pressure head of Water converts into kinetic experiment.

3 The results revealed that the Nozzle -to-throat area energy & there is a considerable drop of pressure at the end of ratio was an important parameter to characterize the suction lift Nozzle . Due to this pressure drop suction is created which of the jet pumps, but nominal diameter had a negligible play role. causes the entrainment of another fluid and accomplishes the Index Term Jet Pump, Nominal Dia, Suction lift and pumping of another fluid. The suction fluid in general differs Throat area. from the driving fluid. Now to explain the working principle of jet pump we have I. INTRODUCTION to focus on the components of jet pump. Basically jet-pumps Ajet-pump is a device that uses the venturi effect of a are composed of ve components. The driving Nozzle , suction converging-diverging Nozzle to convert the pressure energy of Nozzle , suction chamber, mixing chamber or throat and a motive fluid into velocity energy which creates a low pressure zone that draws in and entrains a suction fluid.

4 These accessories are used to suck and elevate liquids, gases or granular solids. The efficiency of jet pumps is usually lower than that of conventional pumps but these accessories have some advantages over conventional pumps such as reliable operation, no moving parts, low maintenance cost, long equipment life, low noise level, and feasibility to operate under several ranges of pressure and flow rate. Jet pumps exhibit the beneficial characteristic of being able to convert a high energy, low volume flow into a low energy, high volume flow. They are also able to pump fluids Fig. 1. Components of a jet-pump containing high levels of abrasive material which would diffuser, as schematically shown in Fig. 1. The motive fluid quickly destroy the moving parts of a conventional pump. comes out through the driving Nozzle converting pressure When used to pump well Water , jet pumps also have the energy into velocity, which creates a low pressure zone in the suction chamber.

5 Due to these low pressure suction fluid 1. Senior Lecturer, Mechanical Engineering Program, School of Engineering entrances at the suction chamber, then mixes with driving and Information Technology, University Malaysia Sabah, Kota Kinabalu, 88400 Sabah, Malaysia, Phone: +60146594093, Email: fluid at the mixing chamber. After passing through the mixing chamber, the mixed fluid expands and the velocity is reduced. 2. Lecturer, Department of Mechanical Engineering, Khulna University of This results in recompressing the mixed fluids by converting Engineering and Technology (KUET)., Khulna-9203, Bangladesh Phone 88041769471 Ext. 439, Email: velocity energy back into pressure energy. The motive fluid may be a liquid, steam or any other gases, the entrained 3. Professor, Department of Mechanical Engineering, Khulna University of suction fluid may be a gas, a liquid, a slurry or granular solids.

6 Engineering and Technology (KUET)., Khulna-9203, Bangladesh Phone 88041769471 Ext. 405, Email: 145303-0606-IJMME-IJENS June 2014 IJENS. IJENS. International Journal of Mechanical & Mechatronics Engineering IJMME-IJENS Vol:14 No:03 46. III. DESIGN PROCEDURE. To evaluate the effect of diameter to characterize the suction lift of the jet pumps, it is needed at least two different nominal diameter jet pumps of same Nozzle to throat area ratios. On the other hand to evaluate the effect of Nozzle -to- throat area ratio to characterize the suction lift of the jet pumps, it is needed jet pumps of several Nozzle to throat area ratios of same nominal diameter. Based on these considerations following dimensional jet pumps were made. The construction of jet pump was fully carried out by lathe machine. Nylon was the material of construction.

7 Following are the dimensions of jet pump constructed. V. RESULT & DISCUSSION. For different inlet pressure, value of discharge for different jet pumps (of different nominal diameter & Nozzle -to-throat area ratio) were enlisted, which graphical representation is given below. For different inlet pressure, value of suction pressure for different jet pumps (of different nominal diameter & Nozzle - to-throat area ratio) were enlisted, which graphical representation is given below. IV. EXPERIMENTAL SETUP. A centrifugal pump acted as a feed pump. This pump drew Water from a reservoir. The pump delivered fluid at a rate of litre/sec and at a manometric head of 29m(H2O). A jet pump connected with the pipeline where pressure drop occurred which resulted the suction of fluid. A pressure gauge used at inlet of the jet pump to get the pressure head of driving fluid.

8 A vacuum gauge used at suction entrance to measure the suction pressure created by jet pump. Figure 4 is the representation of Inlet Pressure Vs Discharge 145303-0606-IJMME-IJENS June 2014 IJENS. IJENS. International Journal of Mechanical & Mechatronics Engineering IJMME-IJENS Vol:14 No:03 47. of all six jet pumps of nominal diameter 25mm & 32mm in a (2) (2010) H. Davis and J. R. Cogdell, Calibration program for the 16-foot antenna, Elect. Eng. Res. Lab., Univ. Texas, Austin, single graph. This graph of Figure 4 shows that with the Tech. Memo. NGL-006-69-3, Nov. 15, 1987. increase of nominal diameter discharge of a jet pump increases significantly. Figure 5, which represents the graph of Inlet Pressure Vs Suction Pressure of all six jet pumps of nominal diameter 25mm & 32mm in a single graph, it can easily been seen that Jet Pump of same Nozzle to throat area ratio but of different nominal diameter gives almost same Suction Pressure at different Inlet Pressure.

9 But with the increase of Nozzle to throat area ratio there is a significant increase in Suction Pressure for same nominal diameter jet pump at different Inlet Pressure. It indicates that Nozzle to throat area ratio has the important aspect on characterization of Jet Pumps than the nominal diameter. VI. CONCLUSION. An experimental study was performed on Water jet pumps with different nominal diameters and Nozzle -to-throat area ratios. The results showed that the Suction Pressure is directly dependent on the Inlet Pressure or motive pressure head for all jet pumps. It is interesting to observe that similar behaviors were obtained with the jet pumps with the same Nozzle -to- throat area ratios but with different nominal diameters (D). So, the Nozzle -to-throat area ratio was found to be an important geometrical parameter to characterize the suction lift of the jet pumps, while their nominal diameter had a negligible impact.

10 REFERENCES. [1] Iran E. Lima Neto, Journal of Mechanical Science and Technology 25. (2) (2011) 391~394. [2] A. J. Stepanoff, Centrifugal and axial flow pumps: Theory, design and application, 2nd Ed., John Wiley & Sons, New York (1957). [3] N. H. G. Mueller, Water jet pump, Journal of the Hydraulics Division, ASCE, 90 (3) (1964) 83-113. [4] R. G. Cunningham, A. G. Hansen and T. Y. Na, Jet pump cavitations, J. Basic Eng., ASME 92 (1970) 483-494. [5] T. F. Salam and B. M. Gibbs, Gas and solid discharge from fluidized- bed using a jet pump, Powder Technology, 50 (2) (1987) 111-120. [6] D. Wang and P. W. Wypych, Water -only Performance of proportioning jet pumps for hydraulic transportation of solids, Powder Technology, 84. (1) (1995) 57-64. [7] S. H. Winoto, H. Li and D. A. Shah, Efficiency of jet pumps, Journal of Hydraulic Engineering, ASCE, 126 (2) (2000) 150-156.