Numerical simulation of the oblique water impact of double curvature bodies involving suction and cavitation phenomena

Abstract

The present study aims to assess the capability of a numerical method to model hydrodynamic impacts representative of an aircraft ditching. The considered numerical method is based on the Finite Element explicit solver Radioss and a Coupled Eulerian–Lagrangian approach. The fluid–structure interaction is dealt with using an immersed contact interface and a penalty coupling method. The oblique water impacts of three different fuselage sections have been studied based on the experimental campaigns carried out during the European project SARAH at the High-Speed Ditching Facility of CNR-INM in Rome, Italy. The results are presented in terms of force coefficient, local relative pressure, and free surface elevation. The effect of the coupling stiffness and size of the fluid elements on the numerical results is analysed to assess the robustness of the numerical method. The numerical method shows a satisfying capability to reproduce most of the experimental results. Particular attention is given to the capability of the numerical method to describe the suction and cavitation phenomena. The effect of the specimens’ transversal cross-section, the specimens’ longitudinal curvature and the development of cavitation phenomenon on the hydrodynamic loads are also investigated.