Analysis Of Temperature Field Of Hydraulic Motor Pump And Optimization Of Flow Channel Structure

The new hydraulic motor pump is a new type of power unit highly integrated with the motor and hydraulic pump,and with the advantages of low noise,high power density,small volume and so on,it has a broad application prospect.There are many key technologies that need to be overcome in the motor pump design process.Among them,temperature rise and heat dissipation directly affect the performance and service life of the motor pump,which is one of the issues that need to be considered in the design and research of the motor pump.This paper takes the axial piston hydraulic motor pump as the research object,using CFD method to conduct the coupling analysis of the three-dimensional flow field and temperature field of the motor pump,and study the distribution law of the flow field and temperature field in the motor pump.In addition,the influence of the casing flow passage structure and the stator oil flow passage on the flow field and temperature field of the motor pump is deeply studied,which provides a reference for the design and optimization of the motor pump.Firstly,this article studies the structural characteristics and heat dissipation principle of the motor pump.Then based on the structural characteristics of the motor pump,the loss composition are analyzed,and the loss is calculated according to the structural parameters of the research object as the heat source for the temperature field calculation.Then based on the CFD method,a coupled calculation model of the threedimensional flow field and temperature field of the motor pump was established.The boundary conditions of the motor pump are set according to the actual working conditions of the motor pump,and the flow field and temperature field distribution rules in the motor pump are obtained by simulation.The excessively long oil suction channel and the sudden change of the flow channel section cause a large hydraulic oil pressure loss,which is not conducive to the full oil absorption of the plunger pump;the stator winding area of the motor pump has a higher temperature,and the rotor area has better heat dissipation.The motor pump is highly integrated and has a small space,and the flow channel structure parameters directly affect its heat dissipation efficiency.In order to study the influence of flow channel structure parameters on the flow field and temperature field of the motor pump,this paper combines theoretical analysis and coupled simulation of the flow field and temperature field of the motor pump to analyze the cooling effect of the motor pump under different flow channel structure parameters.The heat dissipation performance of the spiral flow channel is better than that of the axial parallel flow channel,but the hydraulic oil pressure loss caused by it will also be greater;as the number of flow channels increases,the heat dissipation performance of the motor pump will increase,but the hydraulic oil pressure loss will follow Larger;for a rectangular cross-section flow channel with a certain cross-sectional area,when the ratio of the width to the height of the rectangle is 1,the flow resistance of the flow channel is the smallest but the heat dissipation performance of the motor pump is the worst.Aiming at the problem of poor heat dissipation performance of the stator windings,this paper proposes the auxiliary heat dissipation scheme of the stator oil hole flow channel in combination with the heat dissipation principle of the motor pump.The electromagnetic field simulation model of the motor pump is established based on Maxwell software,and the influence of the position of the stator oil hole opening and the diameter of the oil hole on the electromagnetic field of the motor pump is studied.Then,based on the analysis of the oil-passing hole on the electromagnetic performance of the motor pump,four opening schemes are proposed,and then the influence of the position of the oil-passing hole and the diameter of the oil-passing hole on the flow field and temperature field of the motor pump is studied.Without changing the space size of the motor pump,the stator oil hole can effectively improve the heat dissipation performance of the motor pump,which opens up ideas for the improvement of the heat dissipation performance of the motor pump.