The Tilted Rocket Rig: A Rayleigh–Taylor Test Case for RANS Models1

Abstract

Reynolds-Averaged Navier–Stokes (RANS) models remain the most common design tool in a wide variety of fluid mixing applications. This includes variable-density turbulent mixing as occurs in inertial confinement fusion. The present work extends validation of the BHR-2 RANS model for variable-density turbulence to a two-dimensional Rayleigh–Taylor test case, the “tilted-rig.” The combined effects of bulk fluid motion and turbulence model behavior are discussed, and several quantities of interest are shown to demonstrate the capability of a four-equation turbulence model to describe this type of two-dimensional turbulent mixing. More generally, the tilted-rig test problem is shown to be a useful exercise for RANS model validation.