Computational and Experimental Study on the Water-Jet Pump Performance

The effect of operational and geometrical parameters on the jet pump efficiency were determined experimentally and numerically. Numerical investigation was held firstly to determine the effect of diffuser angle, mixing chamber length, pump area ratio and driving nozzle position on the efficiency of jet pump. Commercial computational fluid dynamics (CFD) solver ANSYS FLUENT R 15.0 using SST-turbulence model was used. The numerical results showed that jet pump efficiency increases with decreasing both of diffuser angles and mixing chamber length up to a certain value and then pump efficiency decreases. Also, jet pump efficiency increases with increasing pump area ratio up to a certain value and then pump efficiency decreases. It was found that maximum numerical efficiency is 37.8 % for pump area ratio of 0.271. In addition, the numerical results showed that the optimum relative length of mixing chamber is 5.48 and the optimum value for diffuser angle at which the efficiency is a maximum value is 5º. Experimental tests were conducted to obtain the effects of various operational and geometrical parameters on the performance of the jet pumps. A test rig was constructed using the optimum design from the numerical results. The CFD’s results were found to agree well with actual values obtained from the experimental results.