Experimental Observation of Collision Process Between Converging Shock Wave and Supersonic Jet

Shock wave has the properties of waves that reflect when they collide with objects, walls, and supersonic jet. Focusing on this property, a technique for the combustion of methane-based mixtures using the temperature increase caused by a single reflection of shock waves has been reported. In this paper, we visualize and observe the process of reflection of shock waves emitted from the shock tube between the reflector and the supersonic jet. The Schlieren method is used to visualize the flow field. The lengths of the shock tube's high-pressure and low-pressure chambers are 10 mm and 20 mm, respectively. The diameter of the shock tube is 10 mm. The experimental parameters were the distance between the reflector and open end of the shock tube 80, 100, 120 mm, the pressure ratio between the high and low-pressure chambers of the shock tube 10.7, 22.6, 35.0, 46.0 and the radius of the reflector ∞, 40 mm. From the experiment, it was confirmed that shock waves reflected by the concave reflector converge and impinge on the jet. For other pressure ratios, it was confirmed that the converging shock waves converge at the same location regardless of the distance from open end of the shock tube to the reflector.