Effect of Loading Mode with Constant Speed and Increasing Torque on Diesel Engine Performance
Based on the transient simulation platform of diesel engine,the transient loading characteristics of diesel engine at constant speed are simulated and studied.The results show that when the diesel engine is loaded from 50 N·m to the full load,after loading,the higher speed with the greater the rise rate of turbocharger pres-sure ratio and the intake air flow rate,the shorter the time for the pressure ratio and the intake air flow to reach the stable value,and the intake air response characteristics are improved.Under different speed,the air-fuel ra-tio of diesel engine is limited to 17.5 after a certain time,the lower the speed with the longer the relative limit time,and the increase rate is relatively slow.The load of diesel engine from 50 N·m to full load,due to the lim-itation of air-fuel ratio,the actual torque response is poor.After 1s of loading,the corresponding torque increase rates of 800 r/min,1 100 r/min,1 400 r/min and 1 600 r/min are:73.5,184.6,334.4 and 463.8.At 2 s after loading,the torque of 1400 r/min and 1 600 r/min can reach full load,while the target torque of 800 r/min and 1 600 r/min can be reached after 3 s.In the loading process of the oil engine,combustion process is bad,and transient BSFC is bad.NOx and CO emission is degradation,the NOx and CO emission is bad for low speed.There is also a trade-off relationship between the transient NOx emission and the transient fuel consumption rate.
万方数据
维普
