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Fusion Science and Technology
Latest News
TerraPower begins U.K. regulatory approval process
Seattle-based TerraPower signaled its interest this week in building its Natrium small modular reactor in the United Kingdom, the company announced.
TerraPower sent a letter to the U.K.’s Department for Energy Security and Net Zero, formally establishing its intention to enter the U.K. generic design assessment (GDA) process. This is TerraPower’s first step in deployment of its Natrium technology—a 345-MW sodium fast reactor coupled with a molten salt energy storage unit—on the international stage.
Om Prakash Joneja, Vijay R. Nargundkar
Fusion Science and Technology | Volume 18 | Number 2 | September 1990 | Pages 310-316
Technical Paper | Blanket Engineering | doi.org/10.13182/FST90-A29302
Articles are hosted by Taylor and Francis Online.
Monte Carlo calculations are performed for a full-coverage spherical system consisting of a stainless steel first wall and a lead-beryllium neutron multiplier. All the calculations use the MORSE-CG code, employing the Los Alamos National Laboratory 30-group neutron cross-section set CLAW-IV in P3 approximation. For multiplier thicknesses varying from 3 to 22.5 cm, the ratio of neutrons leaking from the system with and without 1.5-cm-thick stainless steel decreases from 1.48 to 1.41 for lead and from 1.78 to 1.58 for beryllium. For a three-region system consisting of a first wall, multiplier, and a homogeneous mixture of water and natural lithium, the tritium breeding ratio for the stainless steel-beryllium-homogeneous (natural lithium + water) system is only ∼9% more than that of the stainless steel-lead-homogeneous (natural lithium + water) system. Recent measurements and calculations on neutron multiplication suggest a downward correction for Be(n,2n) and an upward correction for Pb(n,2n) in the ENDF/B-IV cross-section set. In light of such changes in cross sections, a comparison is made between beryllium and lead as a multiplier with a stainless steel first wall.
