Research on ramjet-mode combustion organization based on constant-expansion area configuration in RBCC combustor

The experimental and numerical investigations on the combustion organization and performance evaluation of RBCC combustor based on strut injection and primary rocket piloting combustion under ramjet mode have been performed. The experiment shows that the reliable ignition and stable combustion of secondary kerosene fuel by using fuel-rich primary rocket plume as piloting flame have been accomplished under the low total temperature of incoming airflow condition at ramjet mode. Moreover, the CFD simulation has been employed to obtain the detailed information of flowfield characteristics and combustion organization in RBCC combustor, and the results indicate that the thermal coking in the expansion flowpath has been formed due to the concentrated heat release behind the strut injectors. Reasonable heat release distribution along the combustor is important to get better performance. In order to achieve high combustion efficiency, the 'thermal throat' should be located on the rear of the combustor which leads to sufficient heat release by fuel combustion. Furthermore, based on current RBCC combustor configuration, the effects of the position of fuel strut injector have been investigated and the performance optimizations have been conducted.