Transient Thermal Analysis of Brake Disc in Regenerative Braking System Using Finite Element Analysis

This paper proposes a design development process to analyze and optimize the design of a brake rotor for a Formula Student Electric Vehicle so as to minimize its weight and reduce thermal stress by keeping the rotor within its operating temperature during the entire braking duration. In today’s world where lesser energy consumption is essential, regenerative braking plays an important role, and is also a factor in weight reduction of brake discs. Regenerative braking is an effective method to maximize brake disc’s life, minimize pad wear and extend working range of electric vehicles. The proposed technique consists of using a tire model and building mathematical models in a MATLAB environment to find transient vehicle speed, which in turn provides wheel loads, frictional torque, braking power and heat flux to the brake disc as a function of time. The heat flux to brake disc increases its temperature and is dissipated mainly through convection, which is also a time-dependent parameter based on air velocity. The entire transient heat transfer model, which also depends on the geometry, material of the brake rotor and mechanical boundary conditions is setup in ANSYS FLUENT and ANSYS Transient Structural and simulation results are presented. Stress fields for floating rotor and fixed rotor are compared since fastening techniques also play a crucial role. Disc brakes are used in almost all ground vehicles and thus, the given design process is vital as the work presented can be extended and modified as per requirements to incorporate the needs of the specific situations one needs to work upon.