Numerically robust and efficient nonlocal electron transport in 2D DRACO simulations

An improved implicit algorithm\footnote{Private communications with M. Marinak and G. Zimmerman, LLNL.} based on Schurtz, Nicolai and Busquet (SNB) algorithm\footnote{Schurtz, Nicolai and Busquet, ``A nonlocal electron conduction model for multidimensional radiation hydrodynamics codes,'' Phys. Plasmas 7, 4238(2000).} for nonlocal electron transport is presented. Validation with direct drive shock timing experiments\footnote{T. Boehly, et. al., ``Multiple spherically converging shock waves in liquid deuterium,'' Phys. Plasmas 18, 092706(2011).} and verification with the Goncharov nonlocal model\footnote{V. Goncharov, et. al., ``Early stage of implosion in inertial confinement fusion: Shock timing and perturbation evolution,'' Phys. Plasmas 13, 012702(2006).} in 1D LILAC simulations demonstrate the viability of this efficient algorithm for producing 2D lagrangian radiation hydrodynamics direct drive simulations. Additionally, simulations provide strong incentive to further modify key parameters within the SNB theory, namely the ``mean free path.'' An example 2D polar drive simulation to study 2D effects of the nonlocal flux as well as mean free path modifications will also be presented. This research was supported by the University of Rochester Laboratory for Laser Energetics.