Investigation of mixing characteristics of gaseous kerosene scramjet combustor with an oxygen-supplemented strut

The mixing state of the fuel determines whether the scramjet combustor can work with high performance. The flow field structure and mixing characteristics of the supersonic combustor are studied by using large eddy simulation. The combustor is equipped with struts and uses gaseous kerosene as fuel. The particularity of the strut is that a row of holes in the tail edge of the strut can inject oxygen into the combustor to enhance mixing. First, the flow field structure without oxygen supplementation is studied, and the evolution rule of the flow direction vortex is analyzed. Second, the mixing performance of the fuel and oxidant is evaluated using mixing efficiency. The mixing performance of the combustor under different fuel injection momentum flux ratios is discussed. Then, the differences in the mixing characteristics of the combustor with and without supplemental oxygen are compared. The influence of different fuel/oxygen momentum flux ratio combinations on mixing performance and flow field characteristics is considered. The effect of oxygen supplementation on the fuel diffusion volume is given at last. The results of this work show that oxygen supplementation can change the flow field characteristics and fuel transportation, and significantly improve the mixing performance.