Research On YC4W Diesel Engine To Meet China Ⅳ Emission Regulation

The implementation of China IV Emission regulation is a great challenge to theOEM. The OEMs in China are working on technology route selection to meet theemission standards according to the characteristics of their own products. YC4Wdiesel engine is selected for this study. Both simulation and experiment results areobtained on the technology route selection and engine optimization and engineemission. Result shows that EGR system is an effective way to meet China IVemission standards for light duty diesel engines.Main contents of this paper including：Based on research of SCR/EGR system working principle and operatedspecification which are the two main route to meet Euro-IV emission complianceboth in domestic and international according to the real situation in China we cameto a conclusion that EGR technology is suitable for YC4W engine to make it meetingEuro-IV emission compliance.As a result of analysis and comparison testing, it is possible to make YC4Wengine meeting Euro-IV emission compliance by utilizing high pressure EGRsystem/better capacity cooler/reduce air flow speed/increase noble metalcomposition ratio in after treatment system and higher compression ratio combustionchamber design.We got a better uniformity between cylinders by using BOOST and FIREsimulation software to calculate the EGR rate at two working point, through whichthe inhomogeneity has been control within30%between different cylinder.Carry out vehicle simulation test according to various selected working points.Calculation through CURISE software to get14emission working point based onwhich engine performance and fuel economic will be analyzed. Through thementioned testing analysis we found that not only YC4W engine can meet Euro-IVemission compliance but also can get a much more better fuel efficiency as most ofthe engine working points are within low load area.Through comparison testing we optimized EGR rate/pre-injection data andcommon rail pressure. Finally all the data has been confirmed as: EGR open ratio22%, common pressure1050bar, main injection angle2°, pre-injection quantity1.5mg/str, pre-injection interval angle22°.After going through NEDC engine test, all the emission value are within limitation according to Euro-IV emissioncompliance which show that EGR technology is capable to make YC4W enginemeeting Euro-IV emission standard.