EXPERIMENTAL INVESTIGATION OF DEFLAGRATION TO DETONATION TRANSITION IN HYDROCARBON AIR GASEOUS-MIXTURES

The paper presents the results of investigation of deflagration to det onation transition in gas mixtures with exothermic chemical reaction u sing the experimental method of nonintrusive diagnostics of the proces s. Schlieren photochronography in the optical sections in different pl aces of the tube is performed using the laser as a source of light. Ex perimental results of visualization of the transition process in hydro carbon-air gas mixtures show several different flow patterns: (1) The detonation wave originates in the flame zone. (2) The detonation wave originates between the flame zone and primary shock wave. (3) The seco ndary combustion zone originates between primary shock and the flame a nd causes the detonation. (4) Spontaneous flame occurs that leads to t he combustion to detonation transition. The influence of the flame zon e on the originating strong detonation wave is noticed.