2-D MHD calculations for argon double shell experiments on Double Eagle and Saturn

Summary form only given. 2-D MHD calculations for argon double puff Z-pinch implosions in the 200 ns regime are compared with experimental results. The experiments were conducted on DOUBLE EAGLE at about 4 MA peak currents at Maxwell Physics International, and on Saturn at SNL at about 6 MA peak currents. To do the calculations the 2-D MHD code DELTA is employed. DELTA operates on a triangular unstructured mesh. Initial conditions for the implosion are either taken directly from the interferometric measured r,z. profile and/or calculated using a module of DELTA, NOZZLE. The NOZZLE code solves the Navier-Stokes equations for the supersonic transient flow in the actual geometry from plenum to exit. The full 2-D MHD DELTA is then used to follow the implosion dynamics of this initial density profile. A Collisional Radiation Equilibrium Model (CREMIT) is employed to calculate radiation self-consistently. The results of these calculations are compared with the experimentally measured K-shell radiation yield and power, as well as with filtered X-ray pinhole images designed to observe zippering and final pinch radius. Calculations studying the sensitivity of the final implosion to variations in the initial gas density conditions are presented.