利用外部燃料重整系统对天然气燃料进行了重整反应，燃料重整率为12%，将反应后的重整气体通入进气管内与新鲜空气混合，再通入气缸内燃烧，以此来比较外部燃料重整掺氢燃烧对天然气发动机性能的影响。试验结果显示：结合外部燃料重整掺氢燃烧，发动机的循环变动明显改善，燃烧持续期缩短，相同工况下的燃料消耗率变化很小；THC排放量在各工况下明显减少，50%扭矩负荷率下相对减少量达到22%； NO_x排放量也有所减少，特别是在低扭矩负荷率下，相对减少量达到15%；由于重整气体本身含有一定量的CO，再加上H2的还原作用，导致CO的排放量出现了不同程度的上升。

The reforming reaction of natural gas was conducted with the external fuel reforming system and the reforming rate was 12%. The reforming gas after reaction was introduced into the intake pipe and mixed with fresh air, and then charged into the cylinder for combustion so as to compare the influence of external fuel reforming hydrogenmixed combustion on the performance of natural gas engine. The experimental results show that the cycle variation of engine significantly improves, the combustion duration shortens, and the fuel consumption rate under the same working conditions changes little after the application of external fuel reforming hydrogenmixed combustion. THC emissions significantly reduce under different working conditions, and the relative reduction reaches 22% under 50% torque load rate. In addition, NO_x emissions reduce and the relative reduction reaches 15% especially under low loads. However, the CO emissions still has a rise to different degrees because the reforming gas itself contains a certain amount of CO, coupled with hydrogen reduction.