Coupled Simulations of Extreme Fluid-Structure Dynamics

Abstract

This work presents ongoing research on the influence of fluid-structure interaction (FSI) effects on the ductile crack growth in blast-loaded steel plates. Thin steel plates with Xshaped, pre-formed defects are used to allow for large, inelastic strains and ductile fracture. FSI effects were studied by comparing the numerical predictions of the uncoupled and the coupled FSI approach, where experimental data served as a backdrop to evaluate the accuracy of the numerical simulations. Numerical simulations are conducted in the EUROPLEXUS software. The clear conclusion from this study is that ductile fracture and crack propagation are influenced by FSI effects during the dynamic response of the plate. That is, the crack growth was very sensitive to the actual loading on the plate. Moreover, because the increase in CPU cost may be significant when uniformly refining the mesh, adaptive mesh refinement (AMR) was found very promising in reducing the CPU cost and maintaining the solution's accuracy. The performance of AMR is an interesting finding in the view of numerical simulations of coarsely meshed (prior to AMR) shell structures exposed to blast loading.