Force model of flapping foil stabilizers based on CFD parameterization

Abstract

Abstract The study investigates the hydrodynamic characteristics of a three-dimensional flapping foil with the addition of different bias angles to the pitch motion using a computational fluid dynamics (CFD) method. The working mechanisms, in which the bias angle breaks the symmetry motion that results in large lift forces for maneuvering, are modeled as active fin stabilizers. CFD simulations are conducted using an Unsteady Reynolds-averaged Navier–Stokes (URANS) solver utilizing overset meshes, which enables the tracking of large amplitude heaving and pitching motions of flapping foils. Numerical results are compared with experimental data, and the proposed CFD method is verified and validated. A characterization reduced-order hydrodynamic force model of flapping-foil stabilizers is then proposed on the basis of lift force parameterization that is defined through CFD simulations. This model can be used to develop a control system for the damp rolling, heaving, and pitching motions of vehicles. Finally, simulations are performed to verify the accuracy of the established mathematical model.