New GSD Modeling for Air Blast Wave Supported by Non Uniform Flow: I. Modeling

摘要

The goal of this research is to find a way to model complex shock interactions using Geo-metrical Shock Dynamics (GSD) asa more efficient alternative to computationally expensive hydrocodes, such as the CTH. But classical GSD, as initiallydescribed by Whitham [11], describes shock propagations in which the ow immediately behind the shock front is uniform.Many other shock dynamics phenomena in air, such as the Taylor point blast wave, are not characterized by a uniform flowbehind the shock, so Whitham's GSD (WGSD) theory cannot provide an accurate shock simulation. We thus have developeda new expanded GSD (EGSD) model that can portray shock propagation with a non-uniform ow state behind the shock,which can arise from Taylor point blast; from a finite-sized, condensed explosive detonation; etc. We show the accuracy andefficiency of the new model in this paper by showing excellent agreement in the relation between Mach number and shockradius among hydrocode simulations, GSD simulations and theory.