Thermodynamic performance simulation of a twin-screw multiphase pump

Abstract

A twin-screw pump is a positive displacement pump widely used in various applications such as the petroleum, shipbuilding and foodstuff industries. It can pump some special fluids, such as multiphase fluids and non-Newtonian fluids, which cannot be boosted by other kind of pumps. Profile generation, rotor geometry characteristics and mathematical models to predict the backflow within twin screw multiphase pumps are presented in this paper. On the basis of this analysis, the fundamental equations are provided to simulate the working process of the pump. Also presented is a discussion on the relationship between the slippage rate and the differential pressure, suction pressure, gas void fraction and the rotor rotational speed. In order to verify the mathematical model, performance data of a prototype multiphase pump are measured and the pressure generation process is recorded by using a signal analyser. From the comparison between the simulation result and experimental data, it is shown that the model can simulate the working process of a twin-screw multiphase pump successfully.