Fluid-Structure Interaction Simulation of Blast Loading

This paper presents the development of Fluid-Structure Interaction (FSI) coupling code for solving dynamic behavior of structure under blast loading. We have been developed a Semi-Lagrangian CFD code of MARS for solving initiation and detonation phenomena of explosives. In MARS, it is not functional to analyze dynamic structural behavior. A coupling of MARS with Computational Structure Dynamics (CSD) code is sure and steacy way to acquire the capability of the fluid-structure interaction analysis. An explicit Finite-Element Method (FEM) structure solver DYNA3D 2000 is suitable to couple structure solving capability with MARS, so a FSI coupling code for MARS fluid solver and DYNA3D 2000 structure solver was developed. The developed FSI code was adapted to the test problem of dynamic response of the steel pipe under internal blast loading. Air and explosive was modeled using ideal gas EOS and the structure was modeled using Johnson-Cook strength model and Mie-Gruneisen EOS. Explosive has density of 1400 kg/m3 and energy of 5.32 MJ/kg, and other numerical parameters for calculation used typical value. Strain change and radial displacement of circumference were evaluated, and FSI code was validated comparing the numerical results with experimental results.