Immersed Boundary Methodology for Multistep Ice Accretion Using a Level Set

Abstract

The numerical prediction of in-flight ice accretion involves a sequential call to different modules including mesh generation, aerodynamics, droplet trajectories, wall heat transfer, ice accretion, and geometry update. Automation of this process is critical as these solvers are embedded in a time loop that is repeated several times to obtain an accurate ice shape prediction. The robustness of ice accretion tools is often limited by the difficulty of generating meshes on complex ice shapes and also by the geometry update that can exhibit overlaps in concave regions if not treated properly. An immersed boundary method combined with a level set has the potential to alleviate these issues. The objective of this paper is twofold: confirm the potential of this methodology and assess its accuracy against the usual body-fitted approach. The proposed methodology is tested on two-dimensional (2D) rime and glaze ice cases from the 1st AIAA Ice Prediction Workshop, showing good correspondence with the body-fitted approach. The new methodology also performs well for a 2D three-element airfoil configuration when a proper mesh refinement is used. The immersed boundary method combined with the level-set ice accretion provides a viable alternative to the body-fitted approach.