Study On Transient Performance And Emission Control Strategy For Vehicle Diesel Engine Based On WHTC Cycle

As transient state is a common mode of the vehicle diesel engine, traditional bench testing strategy based on steady state do little to ensure transient performance compliance. It is important and necessary for the enterprises to do research on engine transient performance.The objective of this research is to investigate the transient performance of a vehicle diesel engine. This research is based on World Harmonious Transient Cycle. The content is as follows.1) A methodology is described for the evaluation of transient performance, such as dynamic performance, fuel consumption performance, ride performance, transient emission performance, etc.2) Comparison of WHTC and ETC show that WHTC is more applicable to evaluate the emission and fuel economy performance of a city vehicle3) By taking an 8.3 liter- diesel engine as the research object, this paper has focused on the influence factors of WHTC emission and fuel economy performance. The effect of fuel injection control parameters on the emission and fuel economy had been studied. Based on the acceleration process and deceleration process, the variation of diesel engine and SCR after-treatment system parameters has been analyzed. The influence of the dynamic factor has been studied.Based on the above research and calibration, the diesel engine studied in this paper can meet all the requirements of WHTC China IV emission standard.