Pressure evaluation at arbitrary locations in SPH water impact simulations

Abstract

This paper reports the application of the SPH method to the simulation of structures impacting on water with the focus on pressure assessment at arbitrary positions. The study is motivated by the importance of correct and reliable pressure evaluation in aircraft ditching simulations. The presented approach refers to recent developments in the SPH solver of VPS/PAM-CRASH which now allows using dummy particles to probe pressures. Sensitivity studies towards SPH parameters on pressure results are conducted. Pressures near contact interfaces are also compared to the local contact force divided by the surface area. Furthermore, pressure correction methods referred to as Shepard filtering and Rusanov flux, the lowest order approximation of a Riemann solver, are applied and tested. A comparison with results from flat plate ditching experiments published by Smiley [1] is done. Initial validation is based upon results of an experimental campaign of rigid wedge impacts conducted by Battley et al. [2]. Recommendations for best practice are derived from the study and the application to aircraft ditching is discussed.