Three-dimensional HYDRA simulations of National Ignition Facility targets

The performance of a targets designed for the National Ignition Facility (N IF) are simulated in three dimensions using the HYDRA multiphysics radiatio n hydrodynamics code. [M. Marinak , Phys. Plasmas 5, 1125 (1998)] In simula tions of a cylindrical NIF hohlraum that include an imploding capsule, all relevant hohlraum features and the detailed laser illumination pattern, the motion of the wall material inside the hohlraum shows a high degree of axi symmetry. Laser light is able to propagate through the entrance hole for th e required duration of the pulse. Gross hohlraum energetics mirror the resu lts from an axisymmetric simulation. A NIF capsule simulation resolved the full spectrum of the most dangerous modes that grow from surface roughness. Hydrodynamic instabilities evolve into the weakly nonlinear regime. There is no evidence of anomalous low mode growth driven by nonlinear mode coupli ng. (C) 2001 American Institute of Physics.