CAJ | 학술논문

采取仿真预测与实验测量相结合的方法对某款发动机左边盖结构噪声进行分析。用LMS Test.lab测得发动机左边盖振动加速度信号，以此作为激励，导入到Hypermesh中对左边盖进行有限元分析。提取表面振动速度频谱，作为发动机边盖噪声辐射边界条件，运用LMS Virtual. lab对其进行声学仿真，并对噪声辐射仿真结果进行分析。再通过B&K 3560 D型数据前端对左边盖噪声进行测量，用波束成形法对测量结果进行分析，与仿真结果进行对比验证，两者声功率曲线吻合。对左边盖结构进行改进，再对改进后的左边盖进行噪声测量，整体噪声级呈下降趋势，改进效果显著。对边盖结构噪声预测以及整个发动机的降噪有一定参考作用。
채취방진예측여실험측량상결합적방법대모관발동궤좌변개결구조성진행분석。용LMS Test.lab측득발동궤좌변개진동가속도신호，이차작위격려，도입도Hypermesh중대좌변개진행유한원분석。제취표면진동속도빈보，작위발동궤변개조성복사변계조건，운용LMS Virtual. lab대기진행성학방진，병대조성복사방진결과진행분석。재통과B&K 3560 D형수거전단대좌변개조성진행측량，용파속성형법대측량결과진행분석，여방진결과진행대비험증，량자성공솔곡선문합。대좌변개결구진행개진，재대개진후적좌변개진행조성측량，정체조성급정하강추세，개진효과현저。대변개결구조성예측이급정개발동궤적강조유일정삼고작용。
A method combining simulation prediction and experimental measurement is used to analyze the side cover’s structural noise of an engine. The vibration acceleration signal of the left shell of the engine is measured with LMS Test. Lab. This signal is input into the Hypermesh code as an excitation to carry out the finite element analysis for the left shell of the engine. The surface vibration-velocity frequency-spectrum is extracted as the boundary conditions for noise radiation analysis of the engine’s left shell. Using the LMS Virtual. Lab, acoustic simulation of the left shell is done, and the result of the noise radiation is analyzed. The front-terminal of B&K 3560 D data is applied to measure the noise of the left side cover. The measurement result is analyzed with beamforming technology and compared with that of the simulation. It is found that the sound power curves of the two results are in good agreement. Then, the left shell structure is improved, its noise after the improvement is measured and the effect of the improvement is found to be good. This work is of greater reference significance to predict side cover structure-borne noise and reduce the noise of the entire engine.