On Initial Stage of Combustion of Acetylene–Oxygen Mixtures in a Tube

Experimental study of the process of combustion of a premixed acetylene–oxygen mixture diluted with either nitrogen or argon in a circular cross-section tube is conducted by high-speed photography. The behaviour of flame front at the early stage of acceleration is identified. The experimental findings are compared with the theoretical models available in the literature. It is demonstrated that at the initial stage of the accelerated propagation of flame extended along the channel walls—until deceleration—the velocity of the leading tip of the front is effectively described by the exponential relationship proposed in (Clanet and Searby, 1996). The normal (laminar) burning velocity of the stoichiometric acetylene–oxygen mixture diluted with either nitrogen or argon at a reduced initial pressure (8–21 kPa) is identified.