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Industry Update—February 2026
Here is a recap of recent industry happenings:
Supply chain contract signed for Aurora
Oklo, the California-based developer of the Aurora Powerhouse sodium-cooled fast-neutron reactor, has signed a contract with Siemens Energy that is meant to de-risk supply chain and production timeline challenges for Oklo. Under the terms, Siemens will design and deliver the power conversion system for the Powerhouse, which is to be deployed at Idaho National Laboratory.
Temitope A. Taiwo, A. F. Henry
Nuclear Science and Engineering | Volume 92 | Number 1 | January 1986 | Pages 34-41
Technical Paper | doi.org/10.13182/NSE86-A17862
Articles are hosted by Taylor and Francis Online.
The standard point kinetics equations and formally exact expressions for reactivity, prompt neutron lifetime, and effective delayed neutron fractions are derived from the matrix form of the nodal code QUANDRY. Perturbation theory expressions for reactivity based both on the standard quadratic-transverse-leakage form of QUANDRY and on the coarse-mesh finite difference (CMFD) form, made accurate by the use of discontinuity factors, are derived. With three-dimensional CMFD QUANDRY transient calculations taken as numerical standards, the accuracy of several standard point kinetics methods as well as the improved quasi-static method is tested. Results suggest that point kinetics methods are poor for rod ejection calculations, even if a precalculated table of rod worth versus position is used to infer the reactivity contribution of the moving rods. For transients not involving rod motion, the point kinetics equations are more accurate. Use of core-averaged (rather than node-dependent) temperature coefficients, however, can produce significant errors. The quasistatic scheme appears to yield acceptably accurate results but, for the tests run, consistently required more computing time than needed for the full three-dimensional solutions.