Research on combustion performance improvement by strut/wall combined injection in scramjet combustor

Abstract

Strut/wall combined fuel injection scheme was adopted to improve mixing and combustion efficiency in a scramjet combustor fueled with liquid kerosene in the condition of Mach 6. Injectors were placed on the front of the strut and the side wall of the combustor. A series of numerical simulations and experiments were carried out to improve the combustor performance under conditions of different incoming flow velocity, injection methods and fuel distribution ratios. The value of pressure was obtained by pressure sensor and the flame images were captured by the high-speed camera in experiment. By processing and analyzing the basic data, characteristics of fuel mixing and combustion performance were discussed in this paper. Then, the influence mechanism of the strut/wall combined injection on the performance of the combustor was explained based on the performance with influence factors. Results indicated that the mixing and combustion efficiency was related to condition, injection method and nozzle arrangement. The strut/wall combined injection dispersed the heat release, which could reduce the pressure rise and total temperature. The fuel distribution ratio between the strut injection and wall injection is also a key factor affecting the performance of the combustor. These results in this paper are valuable for the combustion organization in the supersonic combustor and the improvement of the combustor performance.