Author(s)

D. Delsart, N. Toso-Pentecôte, A. Vagnot, L. Castelletti, U. Mercurio & S. Alguadich

Abstract

Works presented in this paper have been performed within the GARTEUR Action Group AG15 \“Improvement of SPH methods for application to helicopter ditching” whose overall objective is aimed at assessing analytical tools for the simulation of helicopter impacts on water. It particularly focused on the Smoothed Particle Hydrodynamic (SPH) formulation, which consists of a gridless Lagrangian method and whose main interest, with respect to fluid/structure interaction issues, relies upon the absence of connectivity between the \“particle elements”, thus permitting it to cope with large deformations without generating mesh distortion problems. In the first step, the SPH method was evaluated through the simulation of droplet impact tests onto a rigid plate, performed at two impact velocities (1 m/s and 5 m/s); numerical results were analysed in terms of force and impulsion data and proved to conveniently fit with the test results. In the second step, water impact tests on simple shapes were simulated, including tests on triangular and cylindrical rigid shapes, performed at the Politecnico Di Milano, and vertical drop tests of a deformable metallic cylinder performed at CIRA. For the considered structures and impact conditions, the simulations permitted one to draw a general conclusion in terms of prediction capacities regarding deformations, accelerations and pressure data. Keywords: smooth particles hydrodynamics, water, impact.

Keywords

smooth particles hydrodynamics, water, impact