Use of methane-air and ammonia-air fuel in propulsion injector

The work is devoted to the possibility of using methane-air and ammonia-air fuel in a propulsion injector. The work developed a propulsion system consisting of a combustion chamber and an injector. As an injector, a steamwater jet apparatus (PVSA) is used, designed to ensure the circulation of the coolant in the primary circuit. A feature of such a PVA is the supercritical flow of the medium in the diffuser. Steam for PVA can be obtained by burning methane in air or by burning ammonia in air. Due to the fact that the most significant influence on the velocity of the mixture at the outlet of the diffuser is exerted by the pressure at the inlet to the PVSA, a computational and theoretical study was carried out based on the results of which it was concluded that the minimum pressure at the inlet to the PVSA at which supercritical flow of the mixture at the outlet is possible from the diffuser for ammonia requires significantly more pressure than for methane, but ammonia provides a higher level of speed. An increase in pressure at the inlet to the PVA also leads to an increase in thrust.