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Two steps forward for U.K. advanced nuclear
This week, two significant announcements have emerged from the United Kingdom’s advanced reactor sector.
On June 14, Rolls-Royce, the United Kingdom National Nuclear Laboratory, and the Japan Atomic Energy Agency announced that they had signed two trilateral memorandums of cooperation to collaborate on “advanced modular reactor (AMR) technology, specifically high-temperature gas-cooled reactors (HTGR), and the coated particle fuel these reactors will use.”
Separately, on June 16, Bellevue, Wash.–based TerraPower announced that its Natrium reactor design has been formally submitted for U.K. regulatory review. The company also announced the formation of a new subsidiary, TerraPower UK Ltd.
Douglas C. Hunt, Deanne Dickinson
Nuclear Technology | Volume 30 | Number 2 | August 1976 | Pages 190-214
Technical Paper | Criticality Array Data and Calculational Method / Chemical Processing | doi.org/10.13182/NT76-A31615
Articles are hosted by Taylor and Francis Online.
The , albedo, interaction potential, weighted interaction Oak Ridge Gaseous Diffusion Plant solid-angle, s/v surface density, fraction critical surface density, and equilateral hyperbola methods are compared by attempting to apply them to 14 different example arrays. The example arrays are distinguished by the type of fissile material in the array units and by the number of units in each array. Arrays with units of Pu(95) metal, U(93) metal, damp U(93)O2, dry Pu(95)O2, U(93)O2(NO3)2 solution, Pu(95)(NO3)4 solution, or U(5)O2F2 solution are considered. It is concluded that if the user has access to a Monte Carlo code such as KENO, he is better off using it than any of the other models for criticality evaluations of specific problems. The remainder of the models are most useful in establishing possible designs for a fissile storage or processing facility. The albedo method is found to be the preferred solid-angle technique, while the s/v surface density method and the method are the most comprehensive and useful of the semiempirical techniques. The s/v method is easier to apply and covers more possible contingencies (e.g., array flooding or persons in arrays), while the method is more difficult to use but has added flexibility, broader applicability, and yields more analytical scaling relations between array parameters.