A myriad of different blending or switching functions have been developed to blend Reynolds-averaged Navier–Stokes (RANS) and large-eddy-simulation (LES) models properly in order to prevent issues such as modeled stress depletion. This challenge is a large focus of modern hybrid methods along with generating sufficient turbulent statistics in the Reynolds-averaged to large-eddy-simulation interface. This paper investigates these issues by implementing a variety of blending functions in the NASA OVERFLOW computational fluid dynamics solver and comparing them with the existing length-scale blending models. Scenarios considered include a zero pressure gradient flat plate, subcritical flow around a cylinder, and a supersonic reattaching shear layer. Overall, the eddy-viscosity blending methods produce results similar, if not improved, to their length-scale blending counterparts. In particular, it was found that the entropy function gave more control and stability during the transition from RANS to LES.
Application of Hybrid Reynolds Averaged Navier–Stokes and Large-Eddy-Simulation Eddy Viscosity Blending Methods in OVERFLOW
AIAA Journal ; 60 , 5 ; 2987-3000
2022-05-01
Article (Journal)
Electronic Resource
English
FLUID DYNAMICS - Blending Functions in Hybrid Large-Eddy-Reynolds-Averaged Navier-Stokes Simulations
Online Contents | 2004
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