Experimental study of combustion efficiency and outlet temperature distribution characteristics of a combined evaporative flameholder

In ramjet engines and afterburners, combined stabilizers are employed to achieve effective flame stabilization. This paper designs a combined evaporative flame stabilizer, aimed at enhancing combustion performance and flame propagation under sub-atmospheric conditions. Combustion efficiency and outlet temperature distribution were experimentally studied under varying inlet Mach numbers, temperatures, pressures, and equivalence ratios. Results indicate that combustion efficiency increases with temperature from 600 K to 800 K, initially increases and then decreases with Mach number from 0.11 to 0.19, and decreases with pressure from 0.04 to 0.101 MPa. At an inlet temperature of 600 K, combustion efficiency drops from 55.84 % to 19.36 % as the fuel–air ratio (FAR) increases from 0.008 to 0.044, and then rises to 24.74 % at a FAR of 0.055. Similar outlet temperature distribution characteristics were observed under different inlet conditions. As the Mach number increases, the peak position of the outlet temperature gradually moves from the center to the lower wall. This study provides design guidance and engineering value for improving the combustion performance of flameholders in afterburners or ramjet engine combustion chambers.