Implicit Large eddy simulation of hypersonic boundary-layer transition for a flared cone

Abstract

We present an implicit large eddy simulation (ILES) of hypersonic boundary-layer transition for a flared cone at Mach number 6.0 and Reynolds number $10.8 \times 10^6$. The simulation is performed using a matrix-free discontinuous Galerkin (DG) method and a diagonally implicit Runge-Kutta (DIRK) scheme on graphics processor units (GPUs). A Jacobian-free Newton-Krylov (JFNK) method is used to solve nonlinear systems arising from the discretization of the Navier-Stokes equations. The ILES simulation exhibits the onset of primary and second-mode instabilities, quite zone, followed by transition to turbulence breakdown. These distinct characteristics of hypersonic flows on cone-like geometries are also observed in experiments. The Stanton number distribution and the pressure fluctuation are studied for different freestream intensities and compared with the experimental data. The results suggest that the ILES method is capable of capturing the onset of transition and turbulence breakdown phenomena for hypersonic turbulent flows past a flared cone.