Thermal Evaporation in Blast Waves: A Model for Aneurism Formation in the NRL (Naval Research Laboratory) LASER-HANE Simulation Experiment.

摘要

A model for the development of the pronounced aneurism observed in the NRL LASER-HANE simulation experiment is presented. The model calculates the evaporative mass loss rate off the swept-up blast wave shell due to a thermal conduction front between the shell and the hot interior cavity. This front is limited to the segment of the shell where the self-generated magnetic fields are small. The thin-shell approximation is used to follow the nonlinear dynamics of the conductive and insulated segments, each of which is taken to be part of a spherical surface. The evaporating segment accelerates relative to the remaining part due to the decrease in its total mass and a rocket-like effect. For reasonable parameters the calculated time scale for appearance of the aneurism agrees with the experimental observations. Several suggestions are made for the future experiments to test the present model.