A mixed finite-element finite-difference method for nonlinear fluid-structure interaction dynamics. I. Fluid-rigid structure interaction

摘要

A mixed finite-element finite-difference numerical method is developed to calculate nonlinear fluid-solid interaction problems. In this study, the structure is assumed to be rigid with large motion and the fluid flow is governed by nonlinear, viscous or non-viscous, field equations with nonlinear boundary conditions applied to the free surface and fluid-solid interaction interfaces. A moving coordinate system fixed at a point in the structure is used to describe the fluid flow, and for numerical analysis purposes, an arbitrary Lagrangian-Eulerian mesh system is constructed relative to this moving system. This provides a, convenient method of overcoming the difficulties of matching fluid meshes with large solid motion. Nonlinear numerical equations describing nonlinear fluid-solid interaction dynamics are derived through a numerical discretization scheme of study. A coupling iteration process is used to solve these numerical equations. A selection of numerical examples illustrates the developed mathematical model and through numerical simulations it is shown that the proposed approach is practical and useful. [References: 58]