两点射流间隔时间对爆震波起爆特性影响的数值研究

In order to initiate the detonation waves efficiently, the ignition method of two jets was proposed and utilized to initiate the mixture of H₂/Air in a detonation chamber. The numerical simulation based on H₂/Air 8 species and 19 steps chemical reaction kinetics mechanism was carried out to study the effects of the double-jet interval time caused by jet tubes height difference on detonation initiation. The reliability of the numerical simulation was verified by the experimental results and the calculation results of CEA. The results indicated that the two hot jets detonated the mixed gas in the detonation chamber successfully within a certain range of jet interval time. However the decrease of jet interaction caused by the increase of jet interval time was not beneficial to the initiation of detonation wave. The height of jet tube affected the jet intensity, and the jet intensity gradient was formed near the outlet of the jet tubes during the detonation initiation. The increase of jet tubes height difference ΔH enlarged the intensity difference between two jets, which weakened the jet interaction. The interaction between two jets was caused by the pressure front interaction and the temperature front interaction, and the pressure interaction had a greater influence on the formation of hot spots.