Investigation of thermal choke in rocket ejector mode

Thermal choke active control in rocket ejector mode and ramjet mode was investigated theoretically and experimentally for the integral design of RBCC engine. Theoretic model for possibility analysis of realizing thermal choke was set up. The effect of combustor geometry, heat adding scheme, flow parameters of the primary and secondary mixture on thermal choke was analyzed, A principle of critical Mach number for determining the possibility of reaching thermal choke was proposed. Both theoretical results and experimental results show that it's difficult to reach thermal choke at sea level static for HC-fueled RBCC engine, while it becomes more easily under some flight conditions. Thermal choke with active control was achieved under the flight Mach number 1.2 on the direct-connecting test facilities of NWPU, with the adjustable range up to one quarter of the combustor length.