Abstract:

To solve the radiation noise problem of cabin structure, the vibration and acoustic radiation characteristics from the cabin was calculated by finite element and boundary element methods in time-domain. The FEM model of an analog cabin was established, and the modal test was done. The vibration mode is analyzed numerically and experimentally and validated the accuracy of this model. The experiment on vibration and sound radiation was done, and the acoustic pressure frequency response of the analog cabin was acquired. Transient response of the analog cabin structure was calculated by ANSYS. The response results of the BEM model were input to Virtual Lab, and the radiated acoustic field inside the analog cabin was calculated by indirect boundary element method. Through comparison, the result of simulation is consistent with the experimental data. It shows that this method is feasible and has theoretical guidance meaning for the control of civil aircraft cabin noise.

摘要：

针对机舱结构辐射噪声问题，基于有限元/边界元法，对模拟舱室结构进行辐射声场仿真与试验。首先建立模拟舱室结构的有限元模型，对模拟舱室结构进行模态试验，将仿真计算与模态试验进行对比，验证了有限元模型的正确性。然后进行模拟舱室结构的声辐射试验，得到模拟舱室结构内部的声压频响特性。最后在ANSYS中对模拟舱室结构进行瞬态响应计算，将结构受节点力激励的响应导入Virtual Lab中，采用间接边界元法计算空腔结构内部的辐射声场。仿真与试验有较好的一致性，表明该方法是正确、可行的。

关键词: 声学, 舱室结构, 振动, 噪声辐射, 有限元, 边界元