振动信号在内燃机无损检测中的应用研究

Application Research of Vibration Signals in Non-destructive Test to Internal Combustion Engine

振动信号的测量和分析是一种有效的无损检测发动机故障的方法,本文利用缸盖表面振动信号实现了各缸燃烧差异的快速诊断。为了便于提取故障特征信息,根据发动机的工作过程编写了模拟软件,来区分各激励源。利用时频分析的方法对一个工作循环内的信号进行处理,通过对比时频域上各缸信号的特征来提取故障特征信息。发动机的拆解检验表明,诊断的结果准确,另外这种特征信息提取的方法不需要建立数据库,通过对比各缸的同类信号即可实现,简单易行。

As for non- destructive test method, vibration signals are measured and analyzed to diagnose efficiently engine troubles. This paper introduces an application based on cylinder head vibration signal to diagnose differences of combustion pressure between cylinders. In order to get failure information conveniently, a simulation program which is used to distinguish the excitation sources is made according to the operating principle of the engine. Time - frequency analysis method is used to analyze the data that is sampled in one work cycle as to get the failure information of the engine through contrast to the signal characteristics in the time - frequency domain. The results verify that the diagnosis is correct after the engine is disassembled and inspected. In addition, database is not required because information is received by treatment to signals from cylinders.