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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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Latest News
X-energy receives federal tax credit for TRISO fuel facility
Advanced reactor company X-energy has been awarded $148.5 million in tax credits under the Inflation Reduction Act for construction of its TRISO-X fuel fabrication facility in Oak Ridge, Tenn.
Avner P. Cohen, Roy Perry, Shay I. Heizler
Nuclear Science and Engineering | Volume 192 | Number 2 | November 2018 | Pages 189-207
Technical Paper | doi.org/10.1080/00295639.2018.1499339
Articles are hosted by Taylor and Francis Online.
Modeling the propagation of radiative heat waves in optically thick material using a diffusive approximation is a well-known problem. In optically thin material, classic methods, such as classic diffusion or classic , yield the wrong heat wave propagation behavior, and higher-order approximation might be required, making the solution more difficult to obtain. The asymptotic approximation [Heizler, Nucl. Sci. Eng., Vol. 166, p. 17 (2010)] yields the correct particle velocity but fails to model the correct behavior in highly anisotropic media, such as problems that involve a sharp boundary between media or strong sources. However, the solution for the two-region Milne problem of two adjacent half-spaces divided by a sharp boundary yields a discontinuity in the asymptotic solutions that makes it possible to solve steady-state problems, especially in neutronics. In this work we expand the time-dependent asymptotic approximation to a highly anisotropic medium using the discontinuity jump conditions of the energy density, yielding a modified discontinuous equation in general geometry. We introduce numerical solutions for two fundamental benchmarks in plane symmetry. The results thus obtained are more accurate than those attained by other methods, such as Flux Limiters or Variable Eddington Factors.