Study on the Dynamic Characteristics of the Geometry Throat of RBCC Variable Structure Combustor

In this paper, the combustion flow characteristics and dynamic response process in the combustor of the variable structure RBCC engine in the geometry throat operation process are investigated by dynamic mesh technology, and the engine regulation law and dynamic characteristics are obtained, and the results are expressed as follows: (1) When the geometry throat starts to adjust, a disturbance wave will be transmitted forward, with a period of about 5.3ms, reaching the position of the leading edge of the shock train in isolator and starting to force the shock train to move forward. At the same time, the disturbance wave will affect the combustion flow in the combustor and change the direction of the airflow. (2) After the geometry throat starts to adjust, the pressure in the combustor oscillations, and then it quickly returns to dynamic equilibrium, and the dynamic response time does not exceed 20ms under the flight condition Ma4. (3) The dynamic response time of the combustor to the adjustment of the geometry throat is different at different adjustment speeds, with the increase of the adjustment speed of the geometry throat, the adjustment time increases and the amount of overshoot increases.