Investigation on the Potential Prevention of Autoignition by the Control of HO₂ Radical Formation

Abstract

Prevention of engine knock is a challenge for the improvement of spark ignition engines. In the previous study, it was suggested that the compression due to flame propagation may alter the chemistry and results in preventing autoignition, that is, knock. In this study, a simplified pulsed compression was used for the detailed kinetic analyses of the relevant phenomena. It was found that the peak concentration of HO₂ radical was significantly reduced by the application of the pulsed compression at around first-stage ignition (cool flame). The potential prevention of autoignition and knocking was investigated by zero-dimensional kinetic modeling.