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The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Oklo to collaborate with Atomic Alchemy on isotope production
Fast reactor developer Oklo, which recently went public on the New York Stock Exchange, announced on May 13 that it has signed a memorandum of understanding with Atomic Alchemy to cooperate on the production of radioisotopes for medical, energy, industry, and science applications.
R. R. Romatoski, L. W. Hu
Nuclear Technology | Volume 205 | Number 11 | November 2019 | Pages 1495-1512
Technical Paper | doi.org/10.1080/00295450.2019.1610686
Articles are hosted by Taylor and Francis Online.
An important fluoride-salt-cooled high-temperature reactor (FHR) development step is to design, build, and operate a test reactor. The uncertainties of the coolant thermophysical properties range between 2% and 20%. This study determines the effects of these high uncertainties by incorporating uncertainty propagation in a thermal-hydraulic safety analysis for test reactor licensing. A hot channel thermal-hydraulic model, Monte Carlo statistical sampling uncertainty propagation, and a limiting safety systems settings (LSSS) approach are combined to ensure sufficient margin to fuel and material thermal limits during steady-state operation while incorporating margin for high-uncertainty inputs. The method calculates LSSS parameters to define safe operation.
The methodology is applied to two test reactors currently considered, i.e., China’s first Solid Fueled Thorium Molten Salt Reactor (TMSR-SF1) pebble bed design and Massachusetts Institute of Technology’s Transportable FHR prismatic core design; two candidate coolants, i.e., flibe (LiF-BeF2) and nafzirf (NaF-ZrF4); and forced flow and natural circulation conditions to compare operating regions and LSSS power (maximum power not exceeding any thermal limits). The calculated operating region accounts for uncertainty (2σ) with an LSSS power for forced flows of 25.37 0.72, 22.56 1.15, 21.28 1.48, and 11.32 1.35 MW for pebble flibe, pebble nafzirf, prismatic flibe, and prismatic nafzirf, respectively. The pebble bed has superior heat transfer with an operating region reduced 10% less when switching coolants and 50% smaller uncertainty than the prismatic. The maximum fuel temperature constrains the pebble bed while the maximum coolant temperature constrains the prismatic due to different dominant heat transfer modes. Sensitivity analysis revealed that (1) thermal conductivity and thus conductive heat transfer dominate in the prismatic design while convection is superior in the pebble bed and (2) the impact of thermophysical property uncertainties is ranked and should be considered for experimental measurements in the following order: thermal conductivity, heat capacity, density, and last, viscosity. Broadly, the methodology incorporates uncertainty propagation that can be used to evaluate parametric uncertainties to satisfy guidelines for nonpower reactor licensing applications, and its application shows that the pebble bed is more attractive for thermal-hydraulic safety. Although the method is developed and evaluated for coolant property uncertainties, it is readily applicable for other parameters of interest.