Three dimensional flow structure behind a shock wave discharged from a rectangular cross section shock tube

The structure and behavior of the vortex ring and the secondary shock wave generated behind a shock wave discharged from an open ended rectangular cross section shock tube were investigated experimentally and numerically. For the visualization, double exposure diffuse holographic interferometry was introduced to this phenomenon in addition to double exposure holographic interferometry which had been used previously. For the numerical simulation the TVD finite difference scheme was used. These results indicated that the vortex ring structure which was generated from the shock tube exit was distorted and the secondary shock wave was a complex three dimensional shape.