基于道路载荷谱的柴油机激励分析和台架试验循环研究

基于车辆典型路面行驶产生的道路载荷谱,对发动机的典型运行工况和瞬态行为进行了分析和研究,构建了基于道路载荷的台架运行循环。研究表明:1 500r/min和1 600r/min是车辆行驶过程中柴油机的常用转速,其使用频率远高于其他转速;转速超过1 800r/min时柴油机多数工作于满负荷工况点;柴油机在1 400~1 800r/min运行时主要集中在中高负荷工况,负荷百分比统计值高于60%;整个载荷时间历程中,500~600r/min幅度的转速跃变比例高,且转速最大跃变不会超过1 000r/min。构建的台架运行循环与实际道路载荷强度相似、转速分布类似,能够表征车辆行驶过程中柴油机的激励状态。

Excitation Analysis and Test Cycle Design of Diesel Engine Based on Road Load Spectrum

The typical working conditions and transient behavior were analyzed and studied based on the load history of typical road and the bench test cycle was constructed.The results showed that 1 500 r/min and 1 600 r/min were used frequently dur-ing the driving of vehicle and their used number was higher than that of other speeds.The driving behavior beyond 1 800 r/min made diesel engine run at full loads in most cases.At the range from 1 400 r/min to 1 800 r/min,diesel engine mainly operated in medium and high load conditions and statistic value of load percentage was beyond 60%.The speed jumps between 500 r/min and 600r/min dominated in the whole history of load and the maximum jump of speed was smaller than 1000r/min.The load strength of built test cycle and the speed distribution was similar to that of actual load history,which could represent the exci-tation status of diesel engine during the driving of vehicle.