Research On Hydraulic Structure And Motor Design Of Electronic Water Pump

The electronic water pump integrates control board,motor and other parts.Its operation does not need to be driven by other components.It can work flexibly according to actual needs and has the characteristics of energy saving and high efficiency.As the core component of automobile thermal management system,electronic water pump has been widely used in traditional fuel vehicles and new energy vehicles.This paper mainly focuses on the hydraulic structure and the design of DC brushless motor.The numerical simulation is carried out by using fluid and electromagnetic simulation software.The specific research work is as follows:The market application background,domestic and international development situation of electronic water pump are introduced.The application of electronic water pump in traditional automobile turbocharger cooling,engine cooling and battery cooling of new energy automobile is analyzed according to its structure characteristics.Hydraulic structure modeling and meshing of impeller and volute of electronic water pump.The plane diagrams of impellers and volutes of electronic water pump are designed by hydraulic design software platform PCAD2010;the three-dimensional flow field models of impellers,volutes,inlet,outlet and leakage sections are designed by Creo 3.0;the application of unstructured grids in complex geometric models is expounded.The flow field models are meshed and repaired by ICEM-CFD.The numerical simulation analysis of internal flow field of electronic water pump are introduced.The basic theoretical equation and coupling method of computational fluid dynamics(CFD)are expounded.The general steps of Ansys-Fluent in numerical simulation of coupling characteristics of impeller and volute of electronic water pump are introduced,including pre-treatment,solution and posttreatment.The whole flow field of electronic water pump and the flow field under different flow conditions are analyzed.The static pressure distribution in the impeller inlet area is small,and the performance of the electronic pump is analyzed and predicted,including the head,shaft power and efficiency of the electronic water pump.The advantages and disadvantages of different pole slot numbers of brushless DC motor and the distribution characteristics of stator windings are introduced.The Ansys-Maxwell software is used to analyze the static magnetic field of the motor and calculate the flux density and leakage coefficient of the stator teeth and yoke.The Ansys-Maxwell software is used to analyze the transient magnetic field and optimize the parameters of no-load cogging torque and no-load back EMF of the motor,to simulate whether the permanent magnet produces under the over-current conditions such as blockage.The selection of scroll case and impeller material of electronic water pump,the manufacturing technology of stator and rotor of DC brushless motor are introduced.The flow rate,head,efficiency characteristic parameters of electronic water pump are tested by the comprehensive performance test bench of water pump,and the speed parameters are analyzed and calculated according to the current curve of DC brushless motor.Through the hydraulic structure modeling,numerical simulation analysis of internal flow field,hydraulic performance prediction,DC brushless no-load back EMF,cogging torque analysis,provide the basis for the hydraulic structure of electronic water pump and the design of DC brushless motor.