Influence of Intake Air Pressure and Equivalence Ratio on Low-Temperature Oxidation Reactions and Combustion in an HCCI Engine

Abstract

Supercharging is one way that be cited for expanding the high-load operating limit that is an issue of the homogeneous charge compression ignition (HCCI) engine. Spectroscopic measurements and chemical kinetic simulations were performed in this study to investigate in detail how varying the equivalence ratio by means of the intake air pressure influenced the low-temperature oxidation reactions and main combustion period of HCCI combustion. Experimental and simulation results showed that reducing the equivalence ratio worked to moderate the main combustion period. On the other hand, it was also observed that lowering the equivalence ratio by increasing the intake air pressure resulted in more active low-temperature oxidation reactions.