Numerical algorithms for infinite swept wing ice accretion

A method to simulate ice accretion on swept wings using a two-dimensional Navier-Stokes airflow solver, an Eulerian droplets field formulation and a PDE based thermodynamic model is presented. The current approach, called 2.5D in this paper, is developed by applying a rotation of the system of coordinates to allow simulations on a cut normal to the leading edge. The crossflow velocity component in the simulation plane is computed with the third momentum equation simplified by assuming null derivatives in the spanwise direction. The consistency of the ice accretion software, NSCODE-ICE, is first verified by a grid convergence study on 2D icing cases and an icing layers convergence study on 2D and 2.5D icing simulations. The validation of the approach is performed on an unswept two-dimensional glaze ice case and on a rime ice case. The current 2.5D approach is then validated on an infinite MS-317 swept wing and compared to results from usual semi-empirical infinite swept wing corrections. The new approach succeeds to model the stagnation line where other correction methods fail, leading to a better representation of the convective heat transfer in this area.