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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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The RAIN scale: A good intention that falls short
Radiation protection specialists agree that clear communication of radiation risks remains a vexing challenge that cannot be solved solely by finding new ways to convey technical information.
Earlier this year, an article in Nuclear News described a new radiation risk communication tool, known as the Radiation Index, or, RAIN (“Let it RAIN: A new approach to radiation communication,” NN, Jan. 2025, p. 36). The authors of the article created the RAIN scale to improve radiation risk communication to the general public who are not well-versed in important aspects of radiation exposures, including radiation dose quantities, units, and values; associated health consequences; and the benefits derived from radiation exposures.
Emilian Popov, Boyan Ivanov, Kostadin N. Ivanov, Stilyana Mladenova
Nuclear Technology | Volume 158 | Number 3 | June 2007 | Pages 358-365
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT07-A3847
Articles are hosted by Taylor and Francis Online.
Flow rotation and mixing in a VVER-1000 reactor is investigated using two system codes with three-dimensional fluid-dynamics modeling capabilities (RELAP5-3D and TRACE) and a computational fluid-dynamics (CFD) code (FLUENT). Coarse-mesh models were developed for the system codes, and their applicability is evaluated using the test data as well as the detailed CFD results obtained. Two different temperature zone mapping schemes for comparison with the measured data are proposed and discussed.The test is very informative when used to examine the real loop mixing taking place at a nuclear reactor. The results can be used to improve code input data for correct simulation of the phenomenon. Correctly predicting the flow mixing is very important in regard to the prediction of the local three-dimensional feedback effects depending on the vessel mixing in coupled three-dimensional neutron-kinetic/thermal-hydraulic safety analysis of reactivity insertion accidents such as the main steam line break accident.