反应性气膜对喷管附面层损失的影响

Aiming at the two-dimensional axisymmetric nozzle,the effect of reactive gas film of hydrogen and n-decane on the nozzle boundary layer loss was investigated by numerical simulation.For the two different injection materials,the boundary layer loss of nozzle under different injection ratios of 0%,0.47%,1.07% and 1.42% were analyzed and compared.The results show that the reactive gas film formed by the wall injection significantly reduces the nozzle wall temperature compared to the non-injection case. When the injection ratio increases from 0% to 1.42%,the hydrogen reactive gas film makes the average wall temperature of the nozzle expansion section reduced by 2648.3 K.However,the n-decane reactive gas film causes the average wall temperature of the nozzle expansion section to decrease by 1875.9 K.The n-decane injection is not beneficial to reduce the boundary layer loss of the nozzle, which increases the nozzle boundary layer loss by 504.3%.Meanwhile,hydrogen injection is conducive to reducing the nozzle boundary layer loss,which reduces the boundary layer loss by 38.8%.Therefore,the hydrogen reactive film is more beneficial to improve thermal protection and drag reduction of nozzle boundary layer.