Developing an Infrastructure for Automated Tuning of Hohlraum Simulations

Indirect-drive implosions at the National Ignition Facility (NIF) have demonstrated laboratory

ignition1. Recent advances2 in the Los Alamos radiation-hydrodyamics code xRAGE3,4 have

enabled it to model the integrated hohlraum and implosion dynamics as seen in these

experiments.

xRAGE’s Eulerian hydrodynamics and adaptive mesh refinement provide the unique ability to

study the impacts of multiscale features in hohlraums, such as capsule support tents. The

improvements to xRAGE’s capability that enable the user to model hohlraums include

advancements to heat transfer, 3T equation of state and Non-Local Thermal Equilibrium (NLTE)

physics.

This study will aim to develop an automated methodology for hohlraum simulations within

xRAGE. We will explore how various methodologies for simulating integrated capsule and

hohlraum setups can enable the development of tools in the pursuit of an automated tuning setup

for future hohlraum models to match experimental data.

1 D. Callahan et al., “Achieving a Burning Plasma on the National Ignition Facility (NIF) Laser,” Bulletin of the

American Physical Society AR01.00001 (2021).

2 B. Haines et al., “The development of a high-resolution Eulerian radiation-hydrodynamics simulation capability for

laser-driven hohlraums,” Phys. Plasmas, submitted (2022).

3 M. Gittings et al., “The RAGE radiation-hydrodynamics code,” Comput. Sci. & Discov. 1:015005 (2008).

4 B. Haines et al, “High resolution modeling of indirectly-driven high-convergence layered inertial confinement

fusion capsule implosions,” Phys. Plasmas 24:072709 (2017).