某型柴油机缸盖罩噪声预测及降噪研究

Noise Prediction and Reduction of the Cylinder Head Cover of a Diesel Engine

车辆发动机噪声过大会影响驾驶舒适性,故有必要对其进行降噪。针对某型柴油机缸盖罩噪声突出的问题,采用仿真分析与结构振动声辐射理论相结合的方法,对缸盖罩的振动响应和辐射噪声进行预测。通过识别振动薄弱环节,确定优化方向,提出结构改进方案。根据改进方案得出的研究结果表明,缸盖罩顶面振动响应较大,改进后其总声功率级降低了5.81 dB(A),降噪效果明显。

Large noise of vehicle engines can influence driving comfort.So noise reduction is necessary.In this work,the vibration response and radiation noise of the cylinder head cover of a diesel engine are predicted based on simulation analysis and structural acoustic radiation theory.By identifying the weakness of vibration,the optimization direction is determined,and the structure improvement scheme is put forward.The results show that the vibration response of the top surface of the cylinder head cover is large,and the total acoustic power level is reduced by 5.81 d B(A) after the improvement.It means that the effect of the noise reduction scheme is obvious.