基于模态对标的制动鼓优化设计

Optimization Design of Brake Drum Based on Modal Matching

针对国产制动鼓刹车时存在啸叫的问题,参考进口制动鼓材料特性,基于响应面法对制动鼓固有频率进行优化。首先对制动鼓进行有限元模态分析以及实验模态分析。在此基础上,通过中心组合设计试验方法采样,结合最小二乘法构建制动鼓的前五阶响应面近似模型。采用活动域优化法对材料参数进行优化,并以使前五阶仿真固有频率与试验模态固有频率的相对偏差最小为优化目标,以灰口铸铁的弹性模量和泊松比为变量,以其常用取值为约束条件。相比于初始设计,优化设计后的前五阶固有频率偏差百分比总和由10.82%降至1.01%,显著提高国产化制动鼓与进口制动鼓的模态特性吻合程度。

The modal characteristic of automotive brake drum is a key factor to determine the level of brake noise. In order to lo- calize the imported brake drum which behaves with no brake howling in practice, some automotive enterprise aims at making the modal characteristic of domestic brake drum consistent with the imported one and solving the material properties of the brake drum. This dissertation is based on response surface method to optimize the inherent frequency. Firstly, finite element modal analysis and experimental modal analysis are applied on the brake drum. On this basis, the response surface approximate model of the first five orders is constructed through the central composite design test method for sampling and combined with least square method. Active domain optimization method is used to optimize the parameters of materials. The optimization objective is to make the relative devi- ation of the first five-order simulation inherent frequency and experimental modal inherent frequency minimum, and the variable is the elastic modulus and Poisson ratio of gray cast and the common values as the constrain conditions. Compared to the initial de- sign, summation of the percentage of first five-order inherent frequency offset is reduced from 10.82% to 1.01% after optimization, which significantly improves the goodness of fit of the modal characteristics of domestic brake drum and imported one.