Designing radiation transport tests: Simulation-driven uncertainty-quantification of the COAX temperature diagnostic

Abstract

One of the difficulties in developing accurate numerical models of radiation flow in a coupled radiation-hydrodynamics setting is accurately modeling the transmission across a boundary layer. The COAX experiment is a platform design to test this transmission including standard radiograph and flux diagnostics as well as a temperature diagnostic measuring the population of excitation levels and ionization states of a dopant embedded within the target material. Using a broad range of simulations, we study the experimental errors in this temperature diagnostic. We conclude with proposed physics experiments that show features that are much stronger than the experimental errors and provide the means to study transport models.

Reduced order models for thermal radiative transfer problems based on moment equations and data-driven approximations of the Eddington tensor

“…Next we investigate the DD-VEF model's performance in capturing the radiation wavefront as it propagates through the spatial domain. Note that the F-C test mimics the class of supersonic radiation shock problems and experiments [72,96,97,98]. One measurement of importance in these experiments concerns the time it takes for the radiation wavefront to reach the radiation-drive-opposite side of the test material [72,97,98].…”

“…Note that the F-C test mimics the class of supersonic radiation shock problems and experiments [72,96,97,98]. One measurement of importance in these experiments concerns the time it takes for the radiation wavefront to reach the radiation-drive-opposite side of the test material [72,97,98]. A measurement of accuracy based on this wavefront-arrival metric can be derived by comparing the TRT solution at the right boundary of the F-C test, where the radiation wavefront propagates towards.…”

“…The next step in this analysis is to consider how well the proposed ROM captures the essential macroscopic physics of the travelling wave. The F-C test problem mimics the important class of high-temperature laser driven radiation shock experiments [88,125,126,127,128]. One metric of particular importance in these studies is the breakout time of radiation [88,126].…”

The Role of Inhomogeneities in Supernova Shock Breakout Emission

“…This S N scheme has been compared in a radiationhydrodynamics setting to an implicit Monte Carlo transport scheme coupled to our same hydrodynamics package. In general, there is good agreement between these two methods (Fryer et al 2020), with only mild differences when modeling energy transport across material boundaries. These differences are minimal and believed to be due to artificial transport caused by the simplified re-emission term in the implicit Monte Carlo package.…”