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http://www.sandia.gov/NNSA/ASC/enews/1207/1207b61.html
A publication of the Office of Advanced Simulation & Computing, NA-121.2, NNSA Defense Programs
HIGH-FIDELITY B61 WEAPON-IN-A-FIRE SENSITIVITY ANALYSIS STUDY COMPLETED
A sensitivity analysis study using massively parallel calculations of a B61 subject to various weapon-in-a-fire scenarios was recently completed on the Thunderbird computer at Sandia National Laboratories. These studies employed Sandia’s Design Through Analysis Realization Team (DART) tools to construct the computational model of the B61, along with Sandia’s Sierra thermal/mechanical simulation software to model the fire environment. A typical run time for one of these Sierra calculations is on the order of 50 CPU-years. In addition, this study included the first-ever coupling of a Sierra fire simulation with Sandia’s DAKOTA uncertainty quantification and optimization software toolkit. This was done to identify the maximum heating conditions for a weapon in a specific fire accident scenario. The maximum heat fluxes predicted by Sierra provide high-fidelity time and space varying boundary conditions that will be used in follow-on Sierra thermal simulations of the B61’s internal components. Overall, these combined high-fidelity fire/thermal Sierra calculations will improve the technical basis understanding of B61 system response to abnormal thermal environments.
A bomb partially buried in snow colored by the Sandia code Fuego predicted contours of instantaneous incident heat flux from a fire.