Experimental Study on Dynamic Combustion Characteristics in Swirl-Stabilized Combustors

An experimental study was performed to investigate the combustion instability characteristics of swirl-stabilized combustors. A premixed gas composed ethylene and air burned under various flow geometric conditions. Experiments were conducted by changing inlet mean velocity, equivalence ratio, swirler vane angle, combustor length. Two dynamic pressure sensors, a hot-wire anemometer, photomultiplier tube installed detect oscillations, velocity perturbations, heat release fluctuations in chambers, respectively. ICCD camera used capture time-averaged flame structure. The objective understand relationship between Rayleigh criterion/the When occurred, oscillations in-phase with oscillations. Even if criterion satisfied, stable low possible. This explained analyzing data. root-mean-square value observed predict region better than that fluctuations. bifurcation structure necessary condition for this combustor. results shed new insight into