一种柴油机示功图曲线光顺处理算法研究

示功图是描述柴油机气缸内气体的压力随着曲轴转角变化而变化的曲线,通过分析示功图曲线,可以获取柴油机燃烧状况和运行状态.柴油机工作过程中,具有噪音大、振动大等特点,使得测量得到的示功图曲线存在大量的干扰信号,严重影响分析精度.针对以上问题,提出了一种消除示功图曲线干扰信号的处理算法,该算法有效地融合了均值滤波、中值滤波、...

Research on a kind of processing algorithm of smoothingfor diesel indicator diagram curve

Indicator diagram is a curve that describes the pressure of the gas in the cylinder of a diesel engine as the crankshaft Anglechanges. The combustion and running state of diesel engine can be obtained by analyzing the indicator diagram curve. Due to thecharacteristics of high noise and vibration in the working process of diesel engine, there are a lot of interference signals in the measuredindicator diagram curve, which seriously affects the accuracy of analysis. In order to solve the above problems, a processing algorithm toeliminate the interference signal of the indicator graph curve is proposed. The algorithm effectively integrates mean filtering, medianfiltering, anomaly data replacement processing algorithm, improved anomaly data local filtering algorithm and five-point cubic smoothingalgorithm, and it can effectively eliminate the interference signal in the indicator diagram curve. A 4190ZLC diesel engine was used toset the engine speed at 945 r/ min, the load rate at 30% and the speed at 1 000 r/ min, and the load rate at 50% for experimentalverification. The results show that the algorithm can effectively filter out the high-frequency interference signals in the indicator diagramdata, and obtain smooth and continuous indicator diagram curve while maintaining a small distortion of the indicator diagram curve.