Comparison of performance of four commonly-used turbulence models in numerically simulating two-dimensional backward-facing step turbulent flows

In the paper, the performances of four commonly-used turbulence models (k-epsilon turbulence model, RNG k-epsilon turbulence model, Realizable k-epsilon turbulence model, and k-omega turbulence model) are compared by using Fluent to numerically simulate two-dimensional backward-facing step turbulent flows with the Reynolds number in the range of 200 to 6500. The numerical simulations give the instantaneous mean flow fields and time-averaged flow fields predicted by each turbulence model for various Reynolds and the relation between the length of the back flow region and the Reynolds number. All numerical results are also compared to the experimental results obtained by Qi et al.