Effect of Nozzle Throat Geometry on Flow Field in Liquid Gas Jet Pump:A Simulation Study

The flow field in a liquid-gas jet pump was mathematically modeled,theoretically analyzed in fluid dynamics,numerically simulated with FLUENT software and experimentally evaluated for design optimization.The influence of the shrinkage half-angle of nozzle throat on the flow-rate ratio,pressure ratio,and gas pumping efficiency was investigated.The distributions of pressure and velocity were calculated.The simulated results show that the shrinkage half-angle has a major impact.For example,as the half-angle increases,the flow-rate ratio changes in a fluctuation-constant mode,the pressure ratio varies in a rapid-increase-slow-decrease manner,peaking at 15 o,and the gas pumping efficiency changes in a rapid-increase-fluctuating-decrease way.The optimized half-angle should be in 7.1°~13.5° range at which the gas-pumping efficiency is estimated to be below 5% of the peak efficiency of liquid-gas jet pump.