Quasi-Steady Convergence of Multistep Navier-Stokes Icing Simulations

A newly developed two-dimensional ice accretion and antiicing simulation code, CANICE2D-NS, is presented. The method is used to predict iced airfoil shapes and performance degradation with a multistep approach. A multiblock Navier-Stokes code, NSMB, has been coupled with the CANICE2D icing framework, supplementing the existing panel method-based flow solver. Attention is paid to the roughness implementation within the turbulence model and to the convergence of the steady and quasi-steady iterative procedure. The new coupling allows fully automated multilayer icing simulation, whereas also permitting flow analysis and performance prediction of iced airfoils. Effects of uniform surface roughness in quasi-steady ice accretion simulation are analyzed through different validation test cases. The results demonstrates the benefits and robustness of the new framework in predicting ice shapes and aerodynamic performance parameters, as well as iced airfoil surface pressure coefficients. Finally, the convergence of the quasi-steady algorithm is verified and identifies the need for an order of magnitude increase in the number of multitime steps in icing simulations.