Abstract Details
Analysis of Radiative Shock Experiments and Simulations Using Uncertainty Quantification Techniques
Author: Bruce A. Fryxell
Requested Type: Oral Only
Submitted: 2009-03-31 16:42:43
Co-authors: J. Chou, M. Grosskopf, V. Nair, K. Fidkowski, R.P. Drake, M. Adams, B. Mallick, D. Bingham
Contact Info:
University of Michigan
2455 Hayward Street
Ann Arbor, MI 48109
USA
Abstract Text:
The CRASH Center at the University of Michigan was established to study the properties of radiative shocks, using both detailed radiative-hydrodynamic simulations and experiments at the Omega Laser Facility at the University of Rochester. Comparison of the experimental results with the numerical simulations provides an excellent opportunity to do not only standard verification and validation studies, but to go one step further and provide a formal quantification of the errors and uncertainties in the numerical simulations using statistical uncertainty quantification techniques. There are typically a very large number of input parameters to numerical simulations, each of which has an error or uncertainty associated with it. These inputs can be related, for example, to parameters of the experiment being simulated, quantities such as equations of state or opacities, grid resolution, or tunable parameters within the numerical code, such as adjustable constants in turbulence models. All of these uncertainties propagate through the simulation to provide uncertainties in the results. The goal is to provide a formal framework for the quantification of errors and uncertainties in the numerical simulations. Instead of obtaining a single answer to a calculation, one ends up with a probability distribution for each quantity of interest. Thus each computed value has an associated error bar. We also have experimental results from Omega that can be compared to the simulations. In this case, it is possible to use the data to constrain the uncertainties in the input parameters. This presentation will discuss the uncertainty quantification techniques used at the CRASH center and will show some preliminary results of their use in analyzing results obtained from the CRASH code.
Comments: