Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : September 08, 2024 - September 11, 2024
Ice accretion on aircraft surfaces occurs when supercooled water droplets impact the surface, leading to the formation of ice layers that disrupt airflow, reduce aerodynamic performance, and cause significant safety risks. Thus, accurate prediction of ice accretion is crucial during the aircraft design phase. Supercooled large droplets (SLDs) exhibit splashing and bouncing upon impact due to their larger inertia. At relatively higher ambient temperatures, a thin water film may form on the surface and flow backward due to airflow-induced shear forces, resulting in runback phenomena. Therefore, accurately predicting the surface state (ice or liquid film) is essential to consider the interaction between the flowing water film and impinging droplets. In this study, numerical simulations of SLD icing on a NACA0012 airfoil were conducted. The flow field was computed using the Eulerian approach with the finite difference method (FDM), while the droplet motion was simulated with the Lagrangian approach. Considering the surface state, the simulation accounted for characteristic behaviors of SLD icing such as splash, bounce, and breakup. The shallow water equation (SWE) was introduced to model the water film behavior and simulate runback phenomena. The interaction between droplets and the flowing water film resulted in changes to the actual droplet impact behavior. Additionally, the movement of the water film formed on the surface reproduced complex ice shapes, such as horn shapes.
