双组分混合气态燃料爆震起爆特性

Compared with the gaseous fuels， liquid fuels have better detonability and wider explosive limits. Endothermic cracking reactions of a liquid hydrocarbon fuel occurring at the beginning of combustion under specific temperature and pressure can produce lighter gaseous fuels with a smaller cell size， which has the potential of dramatically reducing the critical initiation energy of the mixture and increasing its detonability. Study on the influence of the gaseous product components and content from the liquid fuel cracking reactions on the deflagration-to-detonation transition (DDT) time and DDT distance was carried out to help obtain better operation condition for generating more detonable mixtures and guide the design of detonation combustion chambers for liquid fuels. An experimental study on the detonation-initiation characteristics of bi-component gaseous fuel acquired from the products of RP-3 aviation kerosene thermal cracking reactions was also conducted via optical method. A comparison of flame propagation velocity in the process of detonation-initiation with different component fuels was carried out. The results showed that the detonation may fail when the methane molar fraction was greater than 60%，and the gaseous unsaturated hydrocarbons such as olefins can enhance the deniability of the mixture fuel. Meanwhile， increasing the equivalence ratio appropriately can enlarge the explosive limit of the mixture fuel.