Optimization Design And Performance Analysis On Down-hole Twin-screw Pump’s Profile

Twin-screw pump is widely used in domestic and foreign oil production industry because of its high efficiency and adaptability,etc.In order to further improve the performance of the screw pump and make it more suitable for the production environment in our country,further research design of screw pump is needed.But there is not enough research on the application of twin-screw pump in the oil production industry.So the rotor of twin-screw pump is the research object of this paper.In this paper,pump’s performance is improved through the optimal design of the rotor’s profile,the flow field characteristics of twin-screw pump are analyzed using finite element method,and the movement law of motion of the flow field in the pump is studied.The rotor of screw pump is the most important part in the system,and the profile of rotor is the key,it can directly affect the performance of the pump.Firstly,the mathematical model of rotor’s profile is established based on the analysis of the existing rotor’s profile.After the analysis of the two rotors meshing conditions,the profile is optimized through B-spline curve fitting and particle swarm optimization,and then the optimized profile is compared with the existing profile.And the related geometrical characteristics of the rotor of screw pump are analyzed.Secondly,three-dimensional solid model of the screw pump’s rotor is established using the optimized rotor profile.According to the principle of screw pump,the model is assembled,and it is carried on the movement simulation design.Then check the interference problem and state of the motion,and analyze the movement rule of pump,then compare with the existing rotor of the screw pump.Finally,based on the theory of computational fluid dynamics,the fluid characteristics of the screw pump are simulated and analyzed.Flow channel model is established,and then the motion characteristics of flow field in the pump are analyzed by fluid simulation.Analyze the pressure and velocity distribution of the flow field,and obtain the influence of internal fluid on the rotor and the efficiency of the whole pump.The purpose of this study is to reduce the leakage in the pump working process and advance the pump performance by optimizing the rotor profile of the twin-screw pump,and make it can work well on the underground oil extraction.