A mathematical model based on unstructured mesh for ice accretion

Abstract

This paper proposes a three-dimensional model to simulate ice accretion on the surface of an aircraft. The model is developed using a prism grid cell, which enables iterations with an unstructured mesh. The model assumes that the impinged water droplets on the surface can form a thin water film, and ice accretion is caused by the flow and solidification of the film. The model is developed by analyzing the conservations of mass, momentum, and energy for the thin water film on the surface. The mass and energy conservation equations of the water film are discretized on the prism grid cell, while the momentum conservation equation, which is simplified using lubrication theory, is integrated along the surface normal direction to obtain an analytical solution for the film velocity. The thicknesses of the water film and ice layer are calculated by iterating the discretized mass and energy conservation equations with the analytical solution of the film velocity. The model is verified by comparing its results with published experimental and numerical data. The results show that the model provides accurate predictions of ice accretion under different conditions, even when using an unstructured grid.