Synergistic promotion of multi-component RP-3 kerosene low-temperature ignition with addition of radical activator

Abstract

Scramjet engines play a vital role in hypersonic vehicles, but they suffer from the ignition issue due to the low reactivity of hydrocarbon fuel when flying at low flight Mach numbers. In this work, the low-temperature ignition performance of multi-component kerosene was significantly improved by only adding 3% borane-dimethyl sulfide (BDMS), resulting in the low-temperature ignition reducing greatly from 620 to 160 °C. This indicates that BDMS was an effective activator for multi-component kerosene. To analyze the low-temperature efficient activation mechanism of multi-component kerosene, paraxylene, ethylcyclohexane, n-decane, and n-tetradecane (each with added 3% BDMS) were studied as they are essential components in kerosene, respectively. The low-temperature ignition performance and the ignition process of n-alkane were significantly improved and changed for a single component of hydrocarbon. There was a synergistic promotion effect for multi-component hydrocarbons with the addition of activator BDMS. BDMS could significantly improve the low-temperature ignition performance and oxidation of ethylcychohexane in the presence of n-tetradecane. The addition of paraxylene promoted the evaporation of the hybrid fuel of n-tetradecane/ethylcyclohexane. The results obtained from this study could help to gain a better understanding of the low-temperature ignition of multi-component kerosene and provide an effective method to solve the scramjet ignition problem at low flight Mach numbers.