稀燃氛围下低碳醇汽油燃烧及爆震特性模拟研究

A simplified five-component mechanism of TRF/ethanol/n-butanol was constructed based on the idea of semi-decoupling,and the combustion process and knock characteristics of a boosted direct injection gasoline engine burning low-carbon alcohol gasoline under a lean-burn combustion atmosphere were simulated and studied.The results show that lean-burn combustion is conducive to reducing the knock intensity,blending n-butanol in a lean-burn atmosphere increases the knock tendency,and different field distributions such as temperature field,free radical field and velocity field are reflected in the knock combustion process,but the change in knock intensity is closely related to the blending ratio,and the physicochemical role of n-butanol occupies different positions under different blending ratios.In addition,lean-burn combustion and doping n-butanol are conducive to improving thermal efficiency and accelerating flame propagation speed,the earliest moment of knock at 15%doping ratio but the intensity of the knock is more moderate,should be based on this use of different strategies to optimize its combustion process to further enhance thermal efficiency.