Numerical Study on Hydrodynamic Performance of Three-Dimensional Oscillating Foil Under Calm Water and Wave Conditions

Abstract The oscillating foil device is the result of long-term observation of nature, which can improve the ship motion in waves. The study on the oscillating foil characteristics of the near-free-surface three-dimensional oscillating foil is important for the navigation performance of high-performance ships. In this paper, the hydrodynamic characteristics of the near-free-surface oscillating foil are calculated using the Finite Volume method. For the present study, the Reynolds-Averaged Navier-Stokes (RANS) method, Volume of Fluid (VOF) model and dynamic overset technology are is adopted. The hydrodynamic performance of the three-dimensional oscillating foil in near-free-surface pure pitch and heave motion is calculated, and the simulation is extended to the condition of regular wave incidence. By studying the hydrodynamic characteristics of the oscillating foil under different non-stationary parameters, average immersion depth, and pitch and heave amplitudes, it is found that there is a turning point in the non-stationary parameters, at which the thrust of the oscillating foil takes a minimum value. Numerical results are validated through the comparison with those of experiments and results from other methods. Furthermore, by exploring the hydrodynamic characteristics of the oscillating foil under different incident regular waves (including various wavelengths and the encountered phase), the hydrodynamic characteristics are obtained.