Experimental research on detonation combustion of acetylene／air mixture igniting by low-temperature plasma

Abstract:

In order to obtain the characterization of AC driven low-temperature plasma initiating the detonation combustion, single-trial detonation has been ignited by low-temperature plasma using acetylene as fuel and the air as oxidant in a 1.5 m long detonation tube and with 60 mm inner diameter. The air and acetylene were filled in the tube according to Dalton law of additive pressure. The air and acetylene would be mixed uniformly by circulating pump. The discharge time of the AC driven low-temperature plasma igniter was 0.5 ms and the energy was 0.2 J once. Meanwhile, propagation characteristics of flame and pressure wave were measured by ion probes and pressure sensors. The experimental results indicated that low-temperature plasma ignited detonation combustion successfully in the mixture when the excess air coefficients were 1.0 and 0.6; the peak pressure values of detonation waves reduced as the initial pressure and the excess air coefficient went down, meanwhile the DDT (Deflagration to Detonation Transition) time and distance increased. Detonation waves cannot be generated in the detonation tube when the excess air coefficient was 1.4.