Numerical study on transient shock wave flows in a tube with a sudden change in its cross section

This paper describes shock-wave flows through a tube with a sudden change in its cross section. A Dispersion Controlled Scheme was used to solve the Euler equations assuming axisymmetry. Computational interferograms were compared with results of shock tube experiments to demonstrate the effectiveness of the numerical code. The code so far validated by the experiments was used to calculate three further cases with variations of the initial shock-wave Mach number and the flow geometry. Complicated transient flow phenomena, such as shock-wave reflection, shock/vortex interaction and shockwave focusing, have been predicted sucessfully. The numerical simulations can be helpful to reveal physical phenomena in the axisymmetric flow, which are somewhat difficult to visualize experimentally. This study is not only important for the basic understanding of shock dynamics but also useful for various engineering applications