Research Of Simulation And Design On Compress Unit Of The Downhole Helico-Axial Multiphase Pump

Downhole helico-axial multiphase pump with double features of the vane pump and compressor, is a new technology of multiphase Pumping,R&D on helico-axial multiphase pump become a hot topic nowadays. Based on major projects for science and technology development and 863 Project, this paper studied the selection rulers and extents of main designing parameters, and determined the main designing parameters, establishing theoretical foundation for the developing of high gas reservoir and coal bed methane field. Three-dimensional model of the pump is completed by Solidworks.In order to complete the numerical simulation on internal flow and operating characteristics of downhole multiphase pump compress unit, establishing perfect CFD analysis model, the three-dimensional turbulent current fields inside the impellers of compression unit for downhole multiphase pumps were simulated by using Fluent and its pretreatment software Gambit. The calculation of multiphase flow is based on the standard k ?εturbulent current mode1, unstructured grid and the Eulerian models. Reference information for the improvement of the pump can be obtained by the analysis of the flow of gas-oil in the channel of pump.According to computational fluid dynamics and finite element analysis software ANSYS, this paper provided a method to analyze the strength of impeller blade for multiphase pump. The paper finally figured out the real pressure distribution on the blade surfaces, and then loaded the pressure distribution to the blade model surfaces for carrying out strength analysis. As it can reflect real force condition of blade surfaces, the method provided in this paper obtains great value to real application.The experiment is carried out to study on the self-designed prototype of the new downhole helico-axial multiphase pump and its external characteristics. The characteristics curve of the prototype under pure water and different GVF conditions were finally obtained, and the result indicates this pump can be efficient in pumping high GVF medium. This paper describes detailed experimental steps and analyzes affection of the changeable void fraction to the external characteriatics of the multiphase pump. The analysis result provides materials for the further development and improvement of multiphase pump.