Multidimensional radiation MHD modeling of argon on deuterium gas puff Z-pinch loads as a neutron source

The 1D radiation MHD simulation studies [A.L. Velikovich, et al., ICOPS2010, Norfork, VA / DPP2010, Chicago, IL] of deuterium (D) double-shell gas-puff Z-pinch implosions driven by the Sandia refurbished Z accelerator have shown that the thermal fusion neutron yields can be increased up to ∼5×10 14 if D in the outer shell is replaced with a dense high-Z gas that can generate a substantial radiative energy loss. The resulting Z-pinch plasmas, however, could be highly susceptible to the development of multidimensional structure and nonuniform gradients due to the RT instabilities. In this study, we present the development of a multiphase multimaterial physics model, and its incorporation into the Mach2+DDTCRE 2D radiation MHD code [Y. K. Chong, et al., ICOPS 2005, Monterey, CA]. The multimaterial DDTCRE radiation transport modeling is necessary to account for the radiation from the outer shell gas. The resulting code will be employed to investigate the effects of multidimensional structure and nonuniform gradients formation and development on the implosion physics and dynamics of argon outer shell and D inner shell (Ar-on-D) gas-puff Z-pinch loads on the refurbished Z. We will characterize various performance metrics, in particular the neutron yields, of the Z-pinch loads as a function of mass ratio and/or radius. A comprehensive comparison analysis of the Ar radiation and neutron emission performance predictions of 1D and 2D radiation MHD models will be made to gauge the efficiency of multimaterial gas-puff loads as a Z-pinch plasma neutron source.