Numerical prediction of wave impact on a cylinder body mounted in a sloshing tank

Abstract

The paper focuses on the CFD simulation of sloshing induced waves and their impact loads on a vertical cylinder body. The sloshing flow is assumed to be described by the Reynolds averaged Navier-Stokes (RANS) equations, where the free-surface dynamics are modeled through a volume of fluid (VOF) scheme. The wave impact loads on the structure for different water depth conditions are compared with the nonlinear potential solutions obtained by using a finite-element-method (FEM). At a relatively deep water condition, the two numerical results show a good agreement because the computed wave kinematics show a similar behavior. The shallower water conditions lead to a different prediction of wave motion before hitting the structure between the two numerical simulations, which results in different peak impact loads. When wave breaking occurs the present CFD simulations under-predict the peaks of impact load because of the energy dissipation by the wave breaking. The pressure peak along the wall of the structure under breaking wave impact can be occasionally higher than those for other wave impact conditions despite the lower wave impact load predicted. The results for the wave motions are analyzed and the wave impact loads estimated by Morison's formula are compared with the two numerical solutions. Copyright ？ 2017 by the International Society of Offshore and Polar Engineers (ISOPE).