Finite Element and Smoothed Particle Hydrodynamics Modeling of Fluid-Structure Interaction Using a Unified Computational Methodology

This study illustrates a comparison of two numerical methods under a unified computational platform for solving fluid-structure interaction (FSI) problems. The first is an arbitrary Lagrangian-Eulerian (ALE)-based fluid model coupled to a structural finite element (FE) method (ALE-FE/FE), and the second is a smoothed particle hydrodynamics (SPH) method coupled to the same structural FE code (SPH/FE). The predictive capabilities and computational efficiency of both the numerical methods are evaluated and validated against a canonical problem of a rapidly varying flow past an elastic gate for which experimental data are available. In both numerical solutions, the fluid flow is governed by the Navier-Stokes equation, and the elastic gate is modeled as a flexible structure. Numerical simulation results show that the ALE-FE/FE continuum approach not only captures the dynamic behavior properly but also predicts the water-free surface profiles and the elastic gate deformations accurately. On the other hand, the coupled purely Lagrangian approach of the SPH/FE under an identical computational platform is found to be less accurate and efficient in predicting the dynamics of the elastic gate motion and the water-free surface profiles.