Stability of shocks relating to the shock ignition inertial fusion energy scheme

Abstract

Motivated by the shock ignition approach to improve the performance of inertial fusion targets, we make a series of studies of the stability of shock waves in planar and converging geometries. We examine stability of shocks moving through distorted material and driving shocks with nonuniform pressure profiles. We then apply a fully 3D perturbation, following this spherically converging shock through collapse to a distorted plane, bounce and reflection into an outgoing perturbed, broadly spherical shock wave. We find broad shock stability even under quite extreme perturbation. V C 2014 AIP Publishing LLC. [http://dx

Studying converging shock collisions in novel hybrid-drive shock ignition geometries

“…Unfortunately, no ignition concept has yet demonstrated this level of symmetry, which means shock fronts in real systems will inevitably carry with them low and mid--mode perturbations while high--mode perturbations on the shock front will rapidly decay due to the inherent stability of planar shocks. Recent 3--D simulations by Davie, Bush, and Evans [21] as well as Haines et al [22] show that the stability properties of shock fronts change for planar (which are stable), converging (unstable), and diverging (more stable) flows. In the high--resolution simulation of Haines et al standard D2 filled polystyrene OMEGA capsules were imploded with a 1.2% P30 drive asymmetry.…”