New Method for Direct Numerical Simulation of Three-Dimensional Ice Accretion

A simple and reasonable mathematical model is developed to simulate ice accretions on three-dimensional bodies directly. Based on the extended heat-transfer model proposed by Myers, this paper brings forward the concept of critical ice thickness as a criterion for the existence of overflow in every icing control volume. Besides, the concept of inner time step is proposed. After each inner time step, the ice-layer thickness and associated icing properties including the ice accretion rate and overflow in all icing control volumes will be updated to make the model more close to the physical reality. Then, the method for deciding the outflow through boundaries of each icing control volume is given based on the contravariant air velocity components just above the icing surface. Ice accretions under typical glaze ice conditions on a GLC-305 swept-wing model are calculated, and the predicted sectional ice shapes are compared with the experimental data as well as LEWICE results. It indicates that the current results reflect some major characteristics of glaze ice and the spanwise overflow phenomenon. Despite some discrepancies between the numerical results and experimental data, the overall growth patterns are reproduced well.