Design Optimization And Performance Analysis Of A Novel Magnetorheological Fluid Brake

Magnetorheological fluid brake is a brake that can control the magnitude of the braking torque by adjusting the current.During the braking process,the smoothness of the brake and the controllability of the braking torque can be achieved.The working characteristics of this kind of brake are very suitable for the intelligent needs of new energy hybrid electric vehicles and driverless cars,so they have attracted the attention of scholars.However,due to the limitation of the shear strength of the magnetorheological fluid and the installation space of the brake,the braking torque of the magnetorheological fluid brake is difficult to meet the automobile braking torque demand.In this paper,by improving the structure of the brake disc and selecting a working medium with good performance,a magnetorheological fluid brake is designed and its structural parameters are optimized.The performance analysis shows that the brake meets the requirements for use.The main research contents include:(1)Taking a small electric vehicle as the research object,by analyzing the torque requirements and installation space of the brake for this model,the three-dimensional structure design of the new magnetorheological fluid brake is carried out,and the shear and fluid dynamics theory of the magnetorheological fluid is based on Based on the calculus,the braking torque model is established,and then the key structural parameters of the brake disc are analyzed to facilitate later optimization.(2)According to the magnetic circuit design theory,the magnetic circuit of the new magnetorheological fluid brake is designed,including the selection of materials and the selection of magnetorheological fluid.The magnetic field analysis module of ANSYS software is used to analyze the direction of magnetic field lines,the distribution of magnetic field strength and magnetic induction intensity,and the magnetic induction intensity of the working gap to determine the rationality of the new magnetorheological fluid brake structure and magnetic circuit design.(3)Aiming at the shortcomings of the new magnetorheological fluid brake,the multi-objective genetic algorithm was optimized for key parameters.Using the mass function and braking torque function of the brake as the optimization objective function,the method is optimized by the combination of finite element analysis and multi-objective genetic algorithm,with the MOGA of MATLAB as the main control program and the APDL analysis program of ANSYS as the auxiliary.Under the premise of dynamic torque requirements,increase the braking torque mass ratio.(4)Analyze the performance of the optimized new magnetorheological fluid brake.Based on the optimized structural parameters of the brake,a Simulink model of braking torque and braking distance is established,and MATLAB is used to simulate and analyze the braking torque and braking distance of the brake.Use ANSYS to analyze the temperature field of different braking conditions of the brake,and observe whether the temperature changes during the braking process to determine whether it meets the working requirements.