Extending the Asay window measurement model to high areal mass shock experiments

An improved analysis technique for the measurement of accumulated mass during an ejecta producing shock physics experiment using the Asay window technique is employed and derived by considering the combined window material and accumulating mass deposits as a variable mass system.  The improved technique introduces an accretion layer component to the analysis that consists of the accumulating surface deposits and includes considerations of this layer in the variable mass system.   The general formulation for the balance of linear momentum allows for the derivation of equations of motions for the combined accretion layer and window material variable mass system in terms of experiment observables.  Dynamic time delays that can occur in dual layer (embedded reflector) Asay windows are accounted for in this method, and accumulated mass and volumetric density are recovered from velocimetry data using an iterative integration technique.   The result of these improvements in the analysis of Asay windows provides for the accurate extension of accumulated mass and volumetric density measurements through the period of bulk material arrival at the window and permits comparisons with radiography.

This work was done by Mission Support and Test Services, LLC, under Contract No. DE-NA0003624 with the U.S. Department of Energy. DOE/NV/03624—1308

Work performed under the auspices of the U.S. DOE by Lawrence Livermore National Laboratory under contract DE-AC52-07NA27344. Lawrence Livermore National Security, LLC. LLNL-ABS-832855.