Water entry of a seaplane section considering the wave effect

Abstract

The landing of a seaplane on the wave is a crucial issue with practical engineering applications in the fields of aeronautical and ocean engineering. The safe landing of seaplanes on wave surfaces prompts an urgent investigation on further understanding the mechanism by which the wings affect loads. This study examines the slamming force characteristics, pressure distributions, and free surface profiles of a two-dimensional seaplane section with varied heel angles into waves, considering different entry velocities, entry locations, and wave steepnesses. The overset mesh technique has been integrated into the waves2Foam toolbox to achieve a numerical wave tank based on the overset mesh. Numerical results for the vertical slamming force, slamming pressure coefficient distribution, and free surface profile were validated against published semi-analytical solutions and laboratory tests. The slamming force during the water entry of the seaplane section under the wave effect shows similar but more complex characteristics than those of the wedge section, manifesting as a phenomenon of multiple peaks. In addition to the bottom slamming of the airframe, localized high-pressure regions appear beneath the wing due to the combined squeezing effect on the air layer by the wing and water particle, which is similar to the wing-in-ground (WIG) effect. Slight sawtooth fluctuations of the wavefront were observed as a consequence of the disturbance of the air layer by the wings.