非道路国四阶段柴油机机内净化试验研究

Experimental research on internal purification of non-road China Ⅳ diesel engine

为降低柴油机NOx、烟度和颗粒物(particulate matter,PM)的排放,秉持设计、仿真、试验一体化的理念,基于PM生成机理,对采用废气再循环(exhaust gas recirculation,EGR)路线非道路国四阶段柴油机进行优化。在合理的试验设计基础上,结合实际路谱制定控制策略,围绕进气均匀性、预喷量、喷油锥角等进行试验及仿真,提出减少进气管壁凹坑、使用厚度为1.0 mm的喷油器垫片、减小EGR阀开度闭环控制的前馈开度等优化措施,有效降低挖掘机尾气排放。

In order to reduce the emissions of NOx,soot and PM of diesel engine,the engine of the non-road China IV excavator is optimized by adopting EGR route based on the PM generation mechanism and adhering to the concept of integration of design,simulation and test.On the basis of design of experiments,combined with the actual road conditions,the spectrum control strategy system is formulated,and the test and simulation are carried out around the intake uniformity,pre-injection amount and injection cone angle.The optimization measures such as reducing the intake pipe wall pit,using injector gasket with thickness of 1.0 mm,and reducing the feed-forward opening of EGR valve closed-loop control are proposed to effectively reduce the exhaust emission of excavator.