Abstract:
"Isentropic Compression with a Rectangular Configuration for Tungstene and Tantalum, Computations and Comparison with Experiments"
This paper details the use of isentropic compression experiments and numerical simulations to study the properties of tungsten and tantalum under high pressure. The primary goal is to benchmark a new electromagnetism module developed for the LS-DYNA finite element program by comparing its predictions to experimental data from Z accelerator shots 1511 and 1555. This new module couples mechanical, thermal, and electromagnetic simulations by solving Maxwell's equations with a Finite Element Method (FEM) for the solid conductors and a Boundary Element Method (BEM) for the surrounding vacuum. The 3D numerical models, created with both coarse and fine meshes, use experimental current profiles as input data to simulate the compression of metal samples in a rectangular anode-cathode configuration. The simulations employed a Steinberg constitutive law and Gruneisen equations of state, assuming constant electrical conductivities and no phase changes. Preliminary results with a coarse mesh show calculated free surface velocities of 3.5 km/s for tungsten and pressures of approximately 2.7 Mbars at the material interface, with ongoing work focused on refining the mesh and comparing results more closely with experimental data.
