超高能点火对重型点燃式甲醇发动机性能、排放影响的试验研究

For spark-ignited internal combustion engines, increasing the ignition energy can increase the combustion speed and extend the operating limit of lean combustion. Based on a ignition intake port injection V-shaped 8-cylinder methanol machine, the differences in performance and emission characteristics of ultra-high energy ignition pairs of 1000r/min and 1500r/min and under different loads were analyzed. The results show that under different engine speeds and loads, ultra-high energy ignition has different effects on the performance and emission of methanol machines. At the same speed, ultra-high energy ignition can effectively improve fuel economy under small load conditions, but due to the influence of the change of charge density in the cylinder, the effect of ignition energy increase on fuel economy improvement weakens with the increase of load.Combustion analysis shows that ultra-high energy ignition can shorten the hysteresis period and advance the phase of the exothermic center of gravity (AI50), and the ignition energy change has almost no effect on the second half of the combustion duration. The effect of ultra-high energy ignition on emissions is: under the condition of increased ignition energy, NOx emissions increase except for 1500r/min small load conditions, while CO emissions increase at low speed and decrease at high speeds, and there is no obvious law in HC emission changes.