Comparative Experimental Investigation of Effusion Cooling Performance on the Annular Combustor Liners at Non-reacting/Reacting Flow Conditions

Three-nozzle annular model combustor is designed to investigate the effusion cooling characteristics under non-reacting and reacting flow conditions. Temperature was measured on both outer and inner liners of the combustor, and then difference of overall cooling effectiveness distribution with or without combustion is analyzed. The effect of coolant to mainstream air flowrate ratio on the overall cooling effectiveness is studied. Results showed that effusion cooling behavior under reacting condition looks distinctly different from that under non-reacting condition. Specifically, cooling effectiveness showed laterally non-uniform distribution and skewed towards the micro rotation direction result from three separate co-swirling flows merge. The most significant phenomenon at reacting flow condition is that low cooling effectiveness region shows up. This is because of the swirling flame impinging on the combustor liners.