车身结构NVH特性多目标拓扑优化研究

建立了某车身地板结构动力学有限元模型,通过分析自由模态固有频率和多点激励下频率响应,验证了车身地板数值分析模型的有效性。以地板结构各激励点最大振动速度的平方和最小化作为目标函数,建立了多目标拓扑优化模型。通过解读优化结果,提出了地板结构改进方案。改进后的车身地板结构各阶自由模态固有频率增加达10%以上,各激励点速度响应大大降低,NVH特性明显提高。研究表明,减小振动速度的多目标拓扑优化设计是一种改善车身NVH特性的有效方法。

Study on multi-objective topology optimization on NVH features of car body

A dynamic finite element model for a car body floor was built,which availability was proven by analyzing both free modal inherent frequency and frequency response under multi-support excitation.A multi-objective topology optimization model was structured with the sum of squares of maximum vibration velocity at excitation points and minimum as the objective function.floor structure improvement plan was proposed by analyzing the optimization results.The free modal inherent frequency for each order of improved car body floor was increased by 10% more.And the NVH character of new floor structure is obviously improved.Research shows that,the multi-objective topology optimization design with vibration velocity reduced is an effective method to improve the NVH character of car body.