A mixed finiteelement finitedifference method for nonlinear fluidstructure interaction dynamics. I. Fluidrigid structure interaction

A mixed finiteelement finitedifference numerical method is developed to calculate nonlinear fluidsolid 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 nonviscous, field equations with nonlinear boundary conditions applied to the free surface and fluidsolid 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 LagrangianEulerian 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 fluidsolid 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 ...