Rapid prediction of submersible hydrodynamic loads in internal solitary waves

Internal solitary waves (ISWs) are ubiquitous in the ocean and can impose substantial operational risks on submersibles. Rapid prediction of the hydrodynamic response of submersibles is essential for safe navigation. A numerical wave tank incorporating the density transport equation was established and validated against observational data. A submersible is modeled using overlapping grids. Simulations covered five wave amplitudes and five submersion depths, resulting in 25 cases. Increases in submersion depth and wave amplitude produce significant changes in the longitudinal force, vertical force, and pitching moment acting on the submersible. Gaussian basis function (longitudinal force) and Gaussian wavelet basis function (vertical force and pitching moment) underpinned regression models for rapid prediction. Subsequently, polynomial fits established quantitative relationships between the model parameters, ISW amplitude, and submergence depth. Finally, the rapid prediction model was validated against independent data.