Numerical Simulation of Shock Wave Interaction with Complexthree- Dimesnional Bodies Using Unstructered Adaptive Grids

This paper describes the application of a new three-dimensional adaptive finite element scheme to the simulation of shock interaction with complex geometry bodies such as tanks, trucks, etc. The classic h-enrichment/coarsening is employed in this scheme in conjunction with a tetrahedal finite element discretization in three dimensions. In order to simplify the refinement/coarsening logic and to be as fast as possible, only one level of refinement/coarsening is allowed per mesh change, which occurs every 4-7 time steps. A high degree of vectorizability has been achieved by pre-sorting the elements and then performing the refinement/coarsening groupwise according to the case at hand. The results of shock wave interaction side-on with generic tank will be examined and discussed in detail. The analysis will identify and discuss several threedimensional shock diffraction processes. Finally, pressure-time histories at several locations will be compared to available experimental data. This comparison should indicate the level of accuracy which may be obtained using the current 3-D model and available computational recourses.