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Validation assessment of hypersonic double-cone flow simulations using uncertainty quantification, sensitivity analysis, and validation metrics

AIAA Scitech 2019 Forum

Kieweg, Sarah K.; Ray, Jaideep R.; Weirs, V.G.; Carnes, Brian C.; Dinzl, Derek J.; Freno, Brian A.; Howard, Micah A.; Phipps, Eric T.; Rider, William J.; Smith, Thomas M.

This is the second of three related conference papers focused on verifying and validating a CFD model for laminar hypersonic flows. The first paper deals with the code verification and solution verification activities. In this paper, we investigate whether the model can accurately simulate laminar, hypersonic experiments of flows over double-cones, conducted in CUBRC’s LENS-I and LENS-XX wind-tunnels. The approach is to use uncertainty quantification and sensitivity analysis, along with a careful examination of experimental uncertainties, to perform validation assessments. The validation assessments use metrics that probabilistically incorporate both parametric (i.e. freestream input) uncertainty and experimental uncertainty. Further validation assessments compare these uncertainties to iterative and convergence uncertainties described in the first paper in our series of related papers. As other researchers have found, the LENS-XX simulations under-predict experimental heat flux measurements in the laminar, attached region of the fore-cone. This is observed for a deterministic simulation, as well as a probabilistic approach to creating an ensemble of simulations derived from CUBRC-provided estimates of uncertainty for freestream conditions. This paper will conclude with possible reasons that simulations cannot bracket experimental observations, and motivate the third paper in our series, which will further examine these possible explanations. The results in this study emphasize the importance of careful measurement of experimental conditions and uncertainty quantification of validation experiments. This study, along with its sister papers, also demonstrates a process of verification, uncertainty quantification, and quantitative validation activities for building and assessing credibility of computational simulations.

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TYPE Conference Poster YEAR 2019
OSTIScopus

Advanced Technology and Mitigation (ATDM) SPARC Re-Entry Code Fiscal Year 2017 Progress and Accomplishments for ECP

Crozier, Paul C.; Howard, Micah A.; Rider, William J.; Freno, Brian A.; Bova, S.W.; Carnes, Brian C.

The SPARC (Sandia Parallel Aerodynamics and Reentry Code) will provide nuclear weapon qualification evidence for the random vibration and thermal environments created by re-entry of a warhead into the earth’s atmosphere. SPARC incorporates the innovative approaches of ATDM projects on several fronts including: effective harnessing of heterogeneous compute nodes using Kokkos, exascale-ready parallel scalability through asynchronous multi-tasking, uncertainty quantification through Sacado integration, implementation of state-of-the-art reentry physics and multiscale models, use of advanced verification and validation methods, and enabling of improved workflows for users. SPARC is being developed primarily for the Department of Energy nuclear weapon program, with additional development and use of the code is being supported by the Department of Defense for conventional weapons programs.

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TYPE Other Report YEAR 2017
DOIDOIOSTIOSTI

High Fidelity Coupling Methods for Blast Response on Thin Shell Structures

Thomas, Jesse D.; Ruggirello, Kevin P.; Love, Edward L.; Rider, William J.; Heinstein, Martin W.

Computational simulation of structures subjected to blast loadings requires integration of computational shock-physics for blast, and structural response with potential for pervasive failure. Current methodologies for this problem space are problematic in terms of efficiency and solution quality. This report details the development of several coupling algorithms for thin shells, with an emphasis on rigorous verification where possible and comparisons to existing methodologies in use at Sandia.

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TYPE SAND Report YEAR 2016
DOIOSTI
Results 1–25 of 105
Results 1–25 of 105