Renormalization Group Model (Yakhot et al., 1989)

The renormalization group theory can be used to derive a model for the subgrid-scale eddy viscosity, which results in an effective subgrid viscosity given by

(35.1)

where

(35.2)

Here, H is the Heaviside function with x as a dummy variable, u is the molecular viscosity, is the mean dissipation rate, and C is a constant taken equal to 73.5. In the low Reynolds number flow region, the effective viscosity is equal to the molecular viscosity, enabling the RNG model to predict flow in near-wall regions more accurately.