柴油机机体辐射噪声预测及低噪声改进设计  

Prediction of engine block's radiation noise and low-noise design

作　　者：杨陈[1] 郝志勇[1] 陈馨蕊[1] 

机构地区：[1]浙江大学机械与能源工程学院,浙江杭州310027

出　　处：《江苏大学学报（自然科学版）》2008年第4期301-303,321,共4页Journal of Jiangsu University：Natural Science Edition

基　　金：国家自然科学基金资助项目(50575203)

摘　　要：为降低柴油机的整机噪声,采用虚拟预测技术对发动机的机体进行了低噪声改进设计.首先建立了由柔性机体、柔性曲轴和刚性连杆、活塞、平衡轴组成的单缸柴油机的多体动力学模型.通过动力学仿真求解得到传递给机体的各种激励力,再根据FEM/BEM耦合的方法求解出整机的辐射声功率级,仿真得到的结果与实验结果吻合较好.最后通过对原机体的结构进行改进设计,不仅降低了整机的声功率级,减小了机体对油底壳、齿轮室盖的激励,还节省了约5 kg的材料.To reduce the diesel engine＇s overall noise, an improved noise reduction design method for the engine block was proposed based on virtual prediction method. A multi-body dynamics model, which ineludes a flexible cylinder block, crankshaft-flywheel and rigid connect rod, piston, and bal-shafts, was set up to perform simulation. The simulation result predicted the forces acting on the engine during operation, such as bearing loads and piston side thrust loads. The FEM/BEM was used to predict the radiated noise of the engine block. The result agrees well with the test data. Finally, by redesigning the structure of original engine block, the radiated sound level was reduced by 1.74 dB （A） , the excitations transferred to oil pan and gear cover were decreased and the block weight was reduced by about 5 kg.

关 键 词：柴油机 机体 多体动力学 有限元法 辐射噪声 

分 类 号：TK421[动力工程及工程热物理—动力机械及工程]