内燃机振动声学特性的预测

Acoustic Behavior Prediction for Internal Combustion Engines

本文提出了在设计的初始阶段预测柴油机结构传递特性和声辐射的方法.在确定发动机结构广义传递函数时,利用了发动机重量和外表面面积与基本参数之间的统计关系式.激励力谱由柴油机工作过程的数学模拟和谱分析得到,发动机结构噪声的声功率谱等于结构广义传递函数和激励力谱的迭加,预测精度对于设计初始阶段是可以接受的.

A method to predict construction transfer behavior and noise radiation of diesel engines at their early stage of design was suggested. Statistical relationships between engine mass as well as outer surface and its basic parameters when engine shape and construction were idealized as a eylindrical shell were used to formulate generalized transfer function (GTF). Sound power spectrum of engine constructional noise was equal to summation of GTF and exciting force spectrum which was obtained by mathematical simulation of diesel in-cylinder processes and spectrum analysis. Accuracy of prediction is acceptable for early stage of engine design.