乘用车变速箱箱体低噪声方法的研究

Research on Low Noise Method of Passenger Car Gearbox

为了改善汽车变速箱振动噪声问题,利用Romax建立变速器传动系统动力学模型,仿真得出变速箱工作时的轴承动态力;对建立的有限元箱体模型进行模态分析,得知箱体比较薄弱区域;由动力学仿真的轴承动态力作为壳体振动响应分析的激励,分析壳体的振动特性;以壳体振动加速度为边界条件,在壳体声学边界元模型基础上利用模态声学传递法计算壳体外声场辐射噪声。通过分析模态参与因子和模态声学贡献量,确定对壳体振动噪声贡献较大的模态,在相应模态振动敏感处优化。结果表明,优化后壳体的振动噪声有所下降,辐射噪声下降了1.4 d B。

In order to improve the vibration and noise of automobile gearbox,by using the Romax,a dynamics model of the transmission drive system is established,and the dynamic bearing force during the operation of the gearbox is obtained by simulation.The modal analysis is performed on the built finite element box model to learn the box relatively weak areas.The dynamic force of the bearing simulation is used as the excitation of the shell vibration response analysis to analyze the shell vibration characteristics,the shell vibration acceleration is used as the boundary condition,and based on the shell acoustic boundary element model,the modal acoustics transfer method is used to calculate the radiated noise from the sound field outside the casing.By analyzing the modal participation factor and the modal acoustic contribution,the modals which contribute more to vibration noise are determined,and optimization is performed in the corresponding modal vibration sensitive place.The results show that the vibration noise of the optimized gearbox decreases and the radiated noise decreases by 1.4 dB.