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Deployable Energy achieves criticality at INL
Ahead of the July 4 deadline set by President Trump in Executive Order 14301, the nuclear community has been following the developments of the Department of Energy’s Reactor Pilot Program, in which companies have been pursuing DOE authorization to build and test their first-of-a-kind nuclear technologies. The EO set an ambitious goal of three reactors achieving criticality by July 4, 2026.
Martin Frank, Jonas Kusch, Thomas Camminady, Cory D. Hauck
Nuclear Science and Engineering | Volume 194 | Number 11 | November 2020 | Pages 971-988
Technical Paper | doi.org/10.1080/00295639.2020.1730665
Articles are hosted by Taylor and Francis Online.
Solving the radiative transfer equation with the discrete ordinates (S) method leads to a nonphysical imprint of the chosen quadrature set on the solution. To mitigate these so-called ray effects, we propose a modification of the S method that we call artificial scattering S (as-S). The method adds an artificial forward-peaked scattering operator that generates angular diffusion to the solution and thereby mitigates ray effects. Similar to artificial viscosity for spatial discretizations, the additional term vanishes as the number of ordinates approaches infinity. Our method allows an efficient implementation of explicit and implicit time integration according to standard S solver technology. For two test cases, we demonstrate a significant reduction of error for the as-S method when compared to the standard S method, both for explicit and implicit computations. Furthermore, we show that a prescribed numerical precision can be reached with less memory due to the reduction in the number of ordinates.