柴油机工作不均匀性的振动检测方法

在某型号装备的柴油机上，采用断缸的方法模拟各缸工作不均匀试验，测量柴油机在不同工作状态下一个工作循环内的机体振动信号。利用局域波分解方法对柴油机振动信号进行时频分析，获得Hilbert时频谱。对柴油机在不同工作状态下振动信号的时频谱进行分析，对各缸段的振动信号频率变化进行统计分析，计算频率偏差，并分析其在不同工作状态下的变化趋势。分析结果表明，利用各缸段振动信号频率变化的偏差可以对柴油机工作不均匀性进行判别。

Approach of Unbalance Operation Detection for Diesel Engines Based on Vibration Measurement

Took experiments on a tank diesel engine to simulate the cylinder work unbalance through breaking the fuel supply, and measured the vibration signals in a working cycle in normal working and misfire conditions. By use of local wave decomposition to analyze the time-frequency feature of diesel vibrations and got Hilbert time-frequency spectrum, so analyzed the frequency according to the time-frequency spectrum in different conditions, calculated the frequency deviation and its trend. The result shows that it is effective to detect the work unbalance of diesel engine through analyzing the frequency deviation of each cylinder.