柴油机工作不均匀性的振动检测方法

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

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。

Experiments to simulate the unbalance working of the cylinders of a tank diesel engine were carried out through breaking the fuel supply. The vibration signals of the shell in a working cycle of the engine were measured in normal working and misfire conditions. Local wave decomposition was used to analyze the time-frequency feature of the engine vibrations, and the Hilbert time-frequency spectrum was obtained. According to the time-frequency spectrum in different working conditions, the frequency deviation and its variation trend were calculated and analyzed. The result shows that it is effective to detect the working unbalance of diesel engines through analyzing the frequency deviation of each cylinder.