Research on combustion characteristics of scramjet combustor with different flight dynamic pressure conditions

Abstract

Combustion characteristics in a scramjet combustor equipped with a thin strut were observed and discussed in this paper. A series of numerical simulations were carried out under different flight dynamic pressure conditions. The parameters of cold flow field and combustion field were used to analyze the combustion characteristics. Based on the basic data, the mixing efficiency, characteristics of flame establishment and propagation as well as combustion field characteristics were discussed in this paper. The influence laws of lower dynamic pressure conditions were further revealed to optimize combustor performance. Results indicated that properly reducing the flight dynamic pressure can enhance the mixing of kerosene. The diffusion of kerosene determined the distribution of combustion zone and heat release. Then, the influencing factor that affected the chemical reaction rate was revealed to shorten chemical reaction time. And the higher flight Mach number made the flame propagation velocity faster and the combustion stability stronger. The fuel mixing became the main factor and low dynamic pressure had little effect on laminar flame propagation velocity under high Mach number conditions. The investigations in this paper are helpful for understanding the combustion characteristics under low dynamic pressure conditions.