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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.
Yina Zhang, Chao Zhang, Jin Jiang
Nuclear Technology | Volume 177 | Number 1 | January 2012 | Pages 98-106
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT12-A13330
Articles are hosted by Taylor and Francis Online.
In this study, computational fluid dynamics simulations are carried out to predict the thermal-hydraulic behavior of supercritical fluids in the subchannel of supercritical water-cooled reactor (SCWR) fuel channels. The thermal-hydraulic behavior of supercritical water in triangular array and square array fuel rod bundles is studied numerically. The effects of various parameters including the pitch-to-diameter ratio and Reynolds number on the flow and the heat transfer characteristics are investigated. It is found that the turbulent mixing coefficient of supercritical water in subchannels is strongly dependent on the fluid bulk temperature and pitch-to-diameter ratio in the vicinity of the pseudo-critical point. To have a higher overall turbulent mixing coefficient, a pitch-to-diameter ratio less than 1.2 is recommended for the design of SCWR. The turbulent mixing coefficient correlation for the triangular array rod bundle is developed in this study based on the numerical results. However, the correlation for the mixing coefficient for the square array rod bundle cannot be expressed as a general correlation.