Numerical Simulation of Shock Induced Turbulence in a Nozzle Flow

In the present paper, a study has been conducted to investigate the shock induced turbulent flow fields and shock/turbulent-boundary layer interaction at the nozzle divergent. Experimental photographs and numerical images are used to investigate on laminar flow structures, transition phenomena, flow separation line as well as viscous boundary layer separation, turbulence structure development and shock/turbulent-boundary layer interaction. It is observed that transition from laminar to turbulent flow separation is shown earlier at the nozzle divergent for the weaker shock wave propagation and the fully developed turbulence is appeared with unsteady flow fluctuations at the end of the nozzle divergent. It is found that the pressure downstream of the separation point showed an unsteady behavior with strong oscillations, and finally jumped to values quite above the ambient pressure. By solving the 2D Navier–Stokes equations with k–ε turbulence model, all turbulent parameters are determined at the end of the nozzle divergent and it is observed that turbulence intensities are almost uniform at the end of the nozzle divergent where slight decay phenomena are appeared along the downstream direction. The skewness of the velocity fluctuations indicates that the present flow appears to be isotropic at the end of the nozzle divergent. © 2013, The Institution of Engineers (India).