Simulation Study On The Combustion And Emissions Of HCCI Engines With Low-ron Gasoline

Homogeneous Charge Compression Ignition(HCCI)engines which method is the homogeneous mixture with compression way before the TDC on spontaneous combustion.It is a better way of high combustion efficiency,low emission pollution for engines.Compared with the high-RON gasoline,the low-RON gasoline has advantages that easy to extract,a better dispersion and low aromatic hydrocarbon pollution.In this article,the low-RON gasoline would be combined with the HCCI technology,using simulation software on the simulation of the low-RON gasoline in an HCCI engine model.In order to the simulation study,a new PRF Skeleton mechanism(44 species and 80reactions)was proposed which is suitable for HCCI engine,in this article.The ignition delay time modified prediction of the new mechanism in a shock tube and the HCCI engine combustion and emissions seemed as a closer result compared with the experimental data,which was proved the veracity of the new mechanism by the CHEMKIN software.To analyze the combustion and emissions of an HCCI engine which used the low-RON gasoline,a whole HCCI engine model which combined with the low-RON gasoline,was built in one-dimensional whole engine software——AVL-BOOST.Firstly,the DI diesel engine model and HCCI engine an HCCI engine which used the low-RON gasoline model were compared with the experimental value respectively.Secondly,the DI diesel engine model and HCCI engine an HCCI engine which used the low-RON gasoline model were compared under the condition of partial load power performance and fuel economy.Finally,in three different of RON gasoline HCCI engine operation condition,combustion Performance and emissions generated simulated research.The results show:Compared the DI diesel engine,the low-RON HCCI engine showed a much better economy performance,under the moderate-load situation.The HCCI engine which used the low-RON gasoline could be only used in the low-load or moderate-load situation,so that the operation condition was limited.Compared with the high-RON gasoline,the low-RON gasoline HCCI engine characteristics is Combustion rate faster,the maximum pressure in cylinder and the cylinder temperature is higher,heat release rate higher.The low-RON gasoline HCCI engine characteristic is HC and CO emissions on the high side and under partial load situation NO emissions is low.Compared with the high-RON gasoline,the low-RON gasoline HCCI engine characteristics is HC and CO emissions significantly lower and NO emissions is slightly higher.