通风盘式制动器热机耦合理论建模与分析

Theoretical Modeling and FEA of Thermo-mechanical Coupling Dynamics of Ventilated Disc Brake

针对制动盘内外侧壁厚不等的通风盘式制动器,基于实测制动副摩擦系数—相对速度试验数据,建立了3维瞬态热-机耦合理论模型及有限元模型,分析了紧急制动工况下制动盘瞬态温度场和法向应力场在径向、周向和法向的分布特征,以及制动盘侧面热弹性变形和厚薄差变化规律.在台架试验中利用热电偶和非接触式位移计测量了制动盘表面温度和热弹性变形,仿真计算结果与试验结果具有良好的一致性.研究结果表明:制动盘瞬态温度、法向应力、热弹性变形之间存在复杂的耦合关系,这主要是由于制动盘通风槽和内、外侧壁厚不等的结构特点以及摩擦、热、机械的相互作用所致.

The theoretical model and FEM of three-dimensional transient thermo-mechanical coupling of the ventilated disc brake with asymmetrical inner and outer disc plate thickness are established,taking into account the real friction-velocity curve of the disc pad couple.Based on the finite elements analysis of the model,the predictions of the thermo-mechanical responses of the brake disc are presented,including disc transient temperature field and normal stress in radial,circular and axial directions,disc lateral deformation and disc thickness variation.Numerical predictions of the disc surface temperature and lateral deformation are compared with experimental measurements obtained by thermocouples and non-contact displacement sensors on test rig,and the simulation results are consistent with the experimental results.The simulation results reveal the complex coupling relations among temperature,normal stress and thermoelastic deformation due to the ventilated slots and asymmetrical inner and outer disc plate thickness,and the interactions among frictional,thermal and mechanical dynamics.