拖拉机驾驶室内低频结构噪声响应分析

Response Analysis of Lower Frequency Structure-borne Noise in Tractor Cab

以某拖拉机驾驶室为研究对象,建立了驾驶室结构和声场有限元模型,将试验测试的驾驶室悬置点加速度信号作为振动激励得到驾驶室强迫运动响应结果。通过基于模态的声固耦合分析得到20~200 Hz范围内驾驶室结构噪声。将计算得到的驾驶室内噪声信号与试验结果进行对比分析。结果表明,仿真计算结果能够反映出激励谱和模态的影响,与试验结果相符。利用此方法预测车辆室内振动噪声水平具有较高的精度,可以为驾驶室声学性能开发提供指导。

The finite element models of structure and acoustic cavity of a tractor cab are established in this paper. Applying the exciting signals of the cab mount to the cab, the results of the forced kinematic frequency response analysis are obtained. The interior structure-borne noise between 20 Hz and 200 Hz is calculated using structure-acoustic coupling analysis based on the mode. The simulated result of the cab interior noise is compared with the measurement result. It is shown that the simulation result can reflect the effect of excitation signal spectrum and acoustic mode, and it matches well with the test result. The method can reach higher accuracy to predict the interior structure-born noise of vehicles, and which can provide a guide for the development of cab acoustic performance.