轿车柴油机气门正时和喷油嘴流量仿真与试验研究

Simulation and Test Study of the Valve Timing and Injector Flow Rate of Diesel Engine for Passenger Car

利用AVLBOOST软件建立了柴油机仿真计算模型,针对喷油嘴流量为710ml/min时全负荷工况下柴油机功率和比油耗进行了计算。计算结果与试验结果的对比表明该计算模型正确有效。在不改变气门升程的情况下,利用该仿真模型对配气正时进行了优化,并在此基础上模拟研究了不同喷油嘴流量对柴油机全负荷性能的影响。结果表明,优化方案可使柴油机中低速扭矩、燃油耗和NOx排放得到改善,且排放可达到欧Ⅳ标准。

A simulation model of diesel engine is established with AVL BOOST software to calculate diesel engine power and specific fuel consumption under the full load cycle of 710 ml/min of injector flow, the comparison between calculation result and test result indicates that tbis computation model is correct and effect. Without changing valve lift, the valve timing is optimized firstly, and then the effect of different fuel injector rate on full-load performance of the diesel engine is studied by simulation. The results show that, not only the low-middle velocity torque and fuel consumption, but also the NOx emission are improved with the optimized proposal, moreover, Euro Ⅳ emission target is satisfied.