盘式制动器热-机耦合渐变可靠性灵敏度分析

为了解决盘式制动器由于摩擦温度过高而导致可靠性降低的问题，以某种汽车的通风盘式制动器为例，进行了热-机耦合渐变可靠性灵敏度分析.利用Workbench的“Coupled Field Transient”模块进行热-机耦合分析，得到了在紧急制动工况下制动器瞬态温度场分布，然后通过与实验结果对比分析，确定有限元模型的准确性.根据制动器最高温度不能超过许用温度的关系推测，利用自适应Kriging代理模型理论建立制动器热-机耦合可靠性功能函数模型.采用自适应Kriging-Monte Carlo 模拟 (adaptive Kriging-Monte Carlo simulation， AK-MCS)方法进行热-机耦合渐变可靠性灵敏度分析，确定设计参数对可靠性的影响程度，并用Monte Carlo法进行结果的验证.结果表明:制动盘单侧厚度对可靠性的影响最为明显，制动盘的导热系数、比热容和散热加强筋厚度次之，制动盘密度影响最小.

Gradual Reliability Sensitivity Analysis of Thermal-Mechanical Coupling of Disc Brakes

In order to solve the problem of reliability decrease due to high friction temperatures， the thermal-mechanical coupling gradual reliability sensitivity analysis is carried out. Taking a car disc brake for example， “Coupled Field Transient” module of Workbench is used to conduct the thermal-mechanical coupling analysis， and transient temperature field distribution of the brake under emergency braking condition is obtained. The accuracy of the finite element model is confirmed by comparing with the experimental results. The adaptive Kriging surrogate model theory is used to establish the reliability performance function model， and the AK-MCS method is used to conduct the gradual reliability sensitivity analysis of thermal-mechanical coupling， and then Monte Carlo method is used to verify calculation results. The results show that the thickness of brake discs has the most obvious influence on the reliability， followed by the thermal conductivity and the specific heat of brake discs， and the thickness of heat-dissipation stiffeners， while influence of the density of brake discs on the reliability is the smallest.