基于FEM/BEM的燃料电池轿车结构声预测和控制

采用有限元(FEM)和边界元(BEM)联合的方法对燃料电池轿车车内结构声进行预测和控制研究,提出了基于FEM/BEM的车内结构声分析方法和流程,建立了车身有限元模型和声学边界元模型,施加实测的激振力计算声学响应,通过试验数据验证了仿真模型,并进行误差分析.提出板件声学贡献分析的指导原则,介绍板件贡献分析原理和方法,进行所关注频率的车身板件声学贡献分析.最后根据分析结果对车身板件采取约束阻尼处理等控制措施,通过虚拟验证改进结果,车内低频噪声明显降低,其中后座椅和前地板改进最明显,证明所提出方法的可行性,达到优化燃料电池轿车车内噪声的目的.

Prediction and Control of Structure-borne Noise for Fuel Cell Vehicle Based on FEM/BEM

In this study,the FCV (fuel cell vehicle) structure-borne noise reduction by the control of body vibration based on FEM/BEM is studied.As to acoustic analysis,in order to get the dynamic behavior of the auto-body structure,a frequency response of body structure is calculated by using FEM.And then,the pressure response of the interior acoustic domain is solved by boundary element method(BEM).Test results show good agreement with simulation results and the error analysis between those is made.As to body panel noise contribution analysis (PNCA),the thoughts and principles of PNCA are set forth and analyzed.Then,the governing principle of selected frequency is determined.Based on the above analysis,PNCA is carried out to point out the direction for body panel improvement.At last,constrained damping treatments are adopted to control body panel vibration.Based on PNCA results,the panel modifications are developed and validated virtually by the above-mentioned method.The simulation results show that the amplitude of low-frequency interior noise reduces and the control of rear seat and front floor improves in FCV structure-borne noise reduction.