Simulating the radiation environment in Z experiments using a 3D view factor code with 1D radiation-hydrodynamics emission modeling

We present an approach for simulating the multidimensional radiation environment in Z-pinch hohlraums at the Sandia Z facility. In this approach we use a three-dimensional (3D) view factor code to compute the incident flux distribution onto all surface elements of the view factor grid. At each surface element, the frequency-dependent re-emission is computed by performing a one-dimensional (1D) radiation-hydrodynamics simulation for the element. The pinch radiation source is treated as a uniformly emitting cylinder, with a size and emission flux given by the experimentally measured time-dependent radius and radiation power. Here, we describe our modeling procedure, and present results from simulations of Z experiments in which a plastic-tamped aluminum foil was located in an open slot in the Z-pinch hohlraum (i.e., the return current structure). We also discuss the sensitivity of the Al plasma conditions to the incident spectrum onto the sample and the re-emission characteristics of the hohlraum walls. (C) 2001 American Institute of Physics.