Numerical investigation of triple gas-puff implosions on the 0.8 MA LTD-III driver*

The work presented here is a continuation of a previous study (http://meetings.aps.org/link/ BAPS.2017.DPP.UP11.128), in which we investigated the effect of tailoring a Staged Z-pinch implosion on the newly constructed LTD-III driver (~0.8 MA, 170 ns) from a single-liner on target to a double-liner on target implosion using the radiation-MHD code MACH2.  Constraining the total mass-per-unit-length (M/L) of the load, we found there was negligible effect of the liner material or mass distribution on final target conditions, suggesting the driving parameter for shock heating in the Staged Z-pinch (on LTD-III) is liner M/L.  The study also considered the effect of axial premagnetization on both shock formation and magneto-Rayleigh-Taylor instability (MRTI) mitigation: we found that a 0.05-0.2 T seed field had little effect on target dynamics, but a 0.1 T field was shown to substantially mitigate MRT growth.  Here we present results from the expanded study, which includes 1- and 2-D results from the rad-MHD code HYDRA, 1-D results from a semi-analytic model of Staged Z-pinch implosions, additional liner configurations for LTD-III, as well as a scaling study of the double-liner concept to multi-MA machines.