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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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World Bank, IAEA partner to fund nuclear energy
The World Bank and the International Atomic Energy Agency signed an agreement last week to cooperate on the construction and financing of advanced nuclear projects in developing countries, marking the first partnership since the bank ended its ban on funding for nuclear energy projects.
Ikuo Kinoshita, Michio Murase, Yoichi Utanohara, Dirk Lucas, Christophe Vallée, and Akio Tomiyama
Nuclear Technology | Volume 187 | Number 1 | July 2014 | Pages 44-56
Technical Paper | Fission Reactors | doi.org/10.13182/NT13-32
Articles are hosted by Taylor and Francis Online.
A numerical study is presented to examine the effects on countercurrent flow limitation (CCFL) of the shape and size of hot leg models with a rectangular cross section. The CCFL was described in terms of Wallis parameters using the channel height H as the characteristic length. Numerical simulations, using the computational fluid dynamics software code FLUENT 6.3.26, were done for the air-water CCFL experiments carried out previously at Helmholtz-Zentrum Dresden-Rossendorf in a 1/3-scale hot leg model with a rectangular channel (H×W = 0.25×0.05 m2), and the results were compared with the air-water CCFL data obtained at Kobe University in a 1/5-scale hot leg model with rectangular cross section (H×W = 0.15×0.01 m2) and the results of simulations. It was found that both the height-to-width ratio and the size of the cross section affected the CCFL characteristics in the Wallis diagram. Comparison of CCFL characteristics in rectangular channels with those in circular channels showed that the hydraulic diameter Dh was a major cross-section geometry term influencing the CCFL characteristics. CCFL constants of the Wallis correlation were ∼0.61 on average for the range 0.05 m ≤ Dh ≤ 0.75 m but became small for Dh ≤ 0.0254 m, and these tendencies were well reproduced by the numerical simulations.
