Control -Oriented Modeling and Experimental Study on Low Temperature Combustion for Diesel Engine

Abstract

Abstract-Diesel low-temperature combustion (LTC) has great potential on ultra-low emissions for internal combustion engine and has been widely researched in recent years. In order to enhance the stability of diesel LTC and improve the transient performance during low temperature combustion and conventional combustion mode switching, accurate prediction of the in-cylinder combustion state in diesel engine is required, and the control strategy should be adjusted accordingly. A controloriented combustion model which consists of the dynamic model of the intake, compression, combustion, expansion and exhaust process of diesel LTC is developed basing on in-cylinder thermodynamic cycle. The model was verified and validated with experimental data. Comparison between the calculation result and the experimental data shows that in LTC combustion mode, the maximum calculation error of indicated mean effective pressure (IMEP) is -5.4%, and the maximum calculation error of crank angle for 50% burnt fuel (CA50) is 6.6%. The results prove that the state parameters of diesel engine could be predicted accurately with this model, which is fundamental for model-based control of diesel low temperature combustion.