Small High-Pressure Chamber Shock Tube

The unsteady supersonic jet formed by the shock tube with small high-pressure section was used as a simple alternative system of pulsed laser ablation. The dynamic of the supersonic jet impinging upon a flat plate are discussed by comparing experimental and calculated results. The experiment and numerical calculation were carried out by schlieren method and by solving the axisymmetric two-dimensional compressible Navier-Stokes equations, respectively. The main parameters are distance between the open end of the shock tube and the flat plate, L/D, and the pressure ratio of the shock tube, P_h/P_b. Where, L, D, P_h and P_b are the distance between the open end of the shock tube and the flat plate, the diameter of the shock tube, pressure of the high and low section of the shock tube, respectively. Collision between the shock wave reflected at the flat plate and the head of supersonic jet takes place. Computational results well predict the experimental dynamic behavior of the shock wave and the supersonic jet. Marked increase in the static pressure on the flat plate under high P_h/P_b and short L/D is observed due to interaction between the shock wave and the unsteady jet flow.