某内燃机车司机室声固耦合噪声仿真分析

Simulate Analysis on Coupled Vibro-Acoustic Noise of Certain Diesel Locomotive Cab

建立某内燃机车的白车身声固耦合有限元模型,对司机室的结构模态、空腔的声学模态以及声固耦合模态进行了分析计算,并在柴油机安装梁处施加单位激励载荷,对司机室前200 Hz的振动及声场响应进行计算分析.针对声场响应的仿真计算结果对声压的峰值产生的原因进行了详细的分析.结果表明:在91、119、131、143、170、198 Hz处由于司机室壁板共振产生了明显的声压峰值,在116、131、143以及164Hz处由于声固耦合使得声压级骤增,需要在实际操作中对该频域加以控制.

A coupled vibro-acoustic finite element model is built based on body-in-white of certain diesel locomotive, the cab structural modal, cavity acoustic modal and coupled vibro-acoustic modal are calculated and analyzed. Unit excitation load is applied on the installing beam of the diesel engine, and the vibration of first 200 Hz and the response to acoustic field are analyzed. The reasons of the peak value of sound pressure is dis- cussed base on the results of sound field simulation calculation. The results show that obvious peak pressure appears at frequency of 91, 119, 131, 143, 170 and 198 Hz due to resonance of the cab wallboard. Acoustic pressure level surges owning to coupled vibro-acoustic at frequency of 116, 131, 143 and 164 Hz which should be controlled in practice.