乘用车车轮销轴声学灵敏度仿真与实验分析

Simulation and Test Analysis of Acoustic Sensitivity of Vehicle Spindles

为分析路面激励引起的车内结构噪声,建立整车结构有限元模型及流体声腔有限元模型;在车轮销轴处施加激励,仿真计算车内对销轴处的声学灵敏度.对仿真结果进行功率叠加,得到车内对销轴处的整体声学灵敏度.该整体声学灵敏度可作为分析路面激励引起的车内结构噪声的依据.在同等边界条件下,对有限元计算结果进行试实验验证.通过模态贡献量分析等方法分析车身结构、后悬架等对车轮销轴声学灵敏度的贡献;对0～200 Hz车内结构噪声处理提出相应的建议.

To analyze the structural noise of vehicles induced by road-surface excitations, a detailed full vehicle structure model and a fluid cavity model were built with finite element method, and the coupled fluid-structure equations were derived. Based on the models, the acoustic sensitivity of a car to the spindle was simulated by applying an excitation force at the rear-axle spindle. The acoustic sensitivity of the whole vehicle to the rear spindle could be acquired by superposition of the simulation results, which could be used to evaluate and analyze the structure noise from the road-surface excitations. Results of the finite element analysis were verified by the tests under the same boundary conditions. Through modal contribution analysis, the contributions of the vehicle structure, rear suspension etc. to the acoustic sensitivity of the spindles were obtained. Some measures for reducing the structural noise in the frequency band from 0 to 200 Hz were suggested.