Separation and reattachment fixed Reynolds-stress model for iced airfoil and wing simulations

Differential Reynolds-stress models (RSMs) are the higher level of Reynolds-averaged Navier-Stokes (RANS) modeling and generally considered to have more potential than eddy viscosity models (EVMs) when applied to separated flows. Nevertheless, some peculiarities have been observed in simulating flows over iced wings. The first is the numerical stability problem caused by non-streamlined wall surfaces. To weaken this, a wall-boundary-natural scale λ=ω−1/8 is introduced into SSG/LRR RSM in this paper. The second is to remedy the problem of the unsatisfactory non-equilibrium characteristic in separating shear layer (SSL), a correction determined by anisotropy of Reynolds normal stresses is developed. The last focuses on the unphysical backbending of the streamlines near stagnation/reattachment (SR) points. Since the SSL correction will worsen this defect, a SR correction is carried out to blended with it. Four two-dimensional iced airfoils and a three-dimensional iced wing are simulated and then the above measures are confirmed to be the positive. •A SSG/LRR Reynolds stress model (RSM) with wall-boundary-natural scale λ=ω−1/8 is robustly applied to simulations of iced airfoils and wing, which confirms that the RSM has greater potential than the EVM (like SST k−ω) for separated flows downstream the ice.•With a new separating shear layer (SSL) correction, the SSG/LRR-λ model produces more accurate results for the aerodynamic coefficients, especially for the maximum lift coefficients.•To further remedy the “backbending” problem, a stagnation/reattachment correction is coupled to the SSL correction (SSL&SR). With the aerodynamic coefficients close to those of SSL version, the final version can obtain a more physical flow structure.