Revisiting the turbulent viscosity parameter C_μ in the k-ϵ model for wall-bounded flows

The k-∈ model is one of the most popular RANS models used by the industry. RANS models leverage the eddy viscosity model where the closure of Reynolds stress is obtained by expressing it as a product of turbulent viscosity and the mean shear. In the k-∈ model, a turbulent viscosity parameter C_μ is required in addition to the turbulent kinetic energy k and its dissipation rate ∈ to obtain turbulent viscosity. In the equilibrium region, where the production of turbulent kinetic energy is nearly equal to its dissipation rate, the value of is taken as 0.09, based on the stress-intensity ratio, obtained using experiments conducted in the late 1960s at very low Reynolds numbers. However, the latest DNS datasets of wall-bounded suggest that the accepted value of C_μ needs revision. In this work, a new value of C_μ is suggested. The new value shows better agreement with the existing DNS datasets and is recommended for modeling wall-bound flows using the k-∈ model.