Effect of primary hole parameters on combustor performance within a slinger combustor

Abstract

This study experimentally investigated the effect of the primary hole on combustor performance in a full annular slinger combustor and verified it by numerical simulation. Six primary hole structure parameters, including different numbers (0, 2, 4, 6) and positions (L/L0, 2/3L/L0, 1/3L/L0), were studied to discuss the trending of total pressure loss, ignition limits, combustion efficiency, and outlet temperature profiles, where the experiment conditions included Mach number, inlet temperature, and fuel–air ratio (FAR). Results show that when the primary hole number decreases, the total pressure loss increases, and combustion efficiency increases to a certain FAR and then drops. Successful ignition FAR and outlet temperature profiles change complicatedly, in which the trend is not consistent with the primary hole number. When L/L0 decreases, ignition limits increase, combustion efficiency drops, and outlet temperature distribution fluctuates along the circumferential direction. Numerical simulation was applied to analyse the universal impact mechanism, which proved that the primary hole parameters impact not only the airflow distribution and jet velocity but also the flow field features. A high FAR or good recirculation zone does not always lead to good performances; the compromise between aerodynamics parameters and structure characteristics determines the combustor performance.