Experimental Study on Combustion Efficiency and Gas Analysis of RDC with Different Blockage Ratio

Rotating detonation experiments with 220 mm outer diameter of combustor are carried out. The experiment used aviation kerosene (RP-3) as fuel and hot air as oxidant. Under the condition that the air flow at the inlet of the combustor is kept constant, when the blockage ratio is 50%, 65%, 75% and 90% respectively, the detonation is successfully initiated and works stably in the experiment. Temperature rise method was used to calculate the combustion efficiency of the rotating detonation combustor outlet. Through sampling, the gas at the rotating detonation combustor outlet was analyzed, and the complete combustion rate based on carbon atoms (CCR) was obtained. There is an optimal blockage ratio and equivalent ratio so that the combustion efficiency and CCR of the rotating detonation combustor reach the maximum value during the experiment. The mode of detonation wave is mainly double-wave collision mode. If the blockage ratio is too large, the propagation mode of detonation wave will change from two wave collision mode to axial pulse mode. At this time, the combustion efficiency and CCR will be greatly reduced. When the blockage ratio is constant, increasing the air flow rate is helpful to improve the combustion efficiency and CCR, and broad the working range of the rotating detonation combustor. The change of air flow rate at combustor inlet has little influence on the wave velocity of detonation wave, and the propagation mode of detonation wave is still two-wave collision mode.