Computational determination of diagnostic signatures of deleterious effects in FRCs undergoing liner compression

A variety of plasma diagnostics will be fielded in experiments at the Air Force Research Laboratory to form, translate, and compress a field reversed plasma configuration (FRC) with an imploding liner over the next three to five years. Information from those diagnostics will be valuable in determining and remedying the causes of suboptimal performance. In order to lay the groundwork for post-shot analysis of the diagnostic suite data we have added models for a number of those diagnostics to our multidimensional simulations of the experiment. Those include axial view diagnostics such as a bolometer, various filtered photodiodes, Faraday rotation measurement, and laser interferometry The signals from the filtered photodiode array are simulated by using emission calculated using TOPS multigroup opacities for the mixtures. In our previous magnetohydrodynamic (MHD) simulations of the full experiment we have examined only optimal conditions, such as uncontaminated deuterium fill, classical transport during compression, etc. To assess the usefulness of the diagnostic suite in separating the various causes of suboptimal performance, we have performed 2-dimensional MACH2 MHD simulations including possibly harmful effects such as plasma contamination from the quartz and aluminum walls and from non-classical Bohm diffusion. The contamination simulations use SESAME format equations of state and Planck mean opacities for mixtures of modest number fractions of deuterium with silicon, oxygen, or aluminum that we generate offline under the assumption of pressure and temperature equilibrium using MIXPAC. The contaminated deuterium is inserted near the appropriate wall and followed by multi-material advection through all phases of the experiment. We will show by simulation results how this diagnostic suite enables us to identify effects severe enough to significantly degrade performance.