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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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Latest News
The current status of heat pipe R&D
Idaho National Laboratory under the Department of Energy–sponsored Microreactor Program recently conducted a comprehensive phenomena identification and ranking table (PIRT) exercise aimed at advancing heat pipe technology for microreactor applications.
Rajesh Mohan, Feroz Ahmed, L. S. Kothari
Nuclear Science and Engineering | Volume 90 | Number 1 | May 1985 | Pages 111-116
Technical Note | doi.org/10.13182/NSE85-A17436
Articles are hosted by Taylor and Francis Online.
The results of a detailed study of a fast neutron diffusion length and pulsed problem in depleted and enriched subcritical uranium assemblies (0.2 to 4% 235U) are reported. The multigroup space- and time-dependent equations are solved using the eigenfunction expansion method. The effect of 235U concentration on space (diffusion length problem) and time (pulsed problem) eigenvalues and eigenfunctions, particularly on the “discrete” eigenvalue and eigenfunction, is discussed. The approach to equilibrium (both in space and in time) of fast neutrons changes with changing 235U concentration.