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Division Spotlight
Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
Standards Program
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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New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
Takashi Takata, Akira Yamaguchi, Kaori Fukuzawa, Kiyoshi Matsubara
Nuclear Science and Engineering | Volume 150 | Number 2 | June 2005 | Pages 221-236
Technical Paper | doi.org/10.13182/NSE05-A2511
Articles are hosted by Taylor and Francis Online.
A numerical methodology of sodium-water reaction (SWR) and a coupling method of SWR and multiphase flow analysis are proposed. Two SWR models are considered. One is a surface reaction model, which assumes that water vapor reacts with liquid sodium at the gas-liquid interface. The surface reaction is likely to be dominant in the initial phase of SWR. The analogy between mass and heat transfers is assumed to evaluate the diffusion-controlled reaction rate. The other is a gas-phase reaction model. If chemical reaction heating due to the surface reaction is large enough to vaporize the liquid sodium, it turns over in the gas-phase reaction. In the gas-phase reaction, water vapor reacts with sodium gas. The reaction mechanisms in the gas-phase reaction are investigated using an ab initio molecular orbital method. The reaction rate of the gas-phase reaction described by the Arrhenius law is obtained from the transition-state theory or the capture theory. The reaction models are employed in a compressible multifluid and one-pressure model using the Highly Simplified Marker and Cell method for multiphase flow analysis. As numerical examples, surface reaction with multiphase flow analysis and simplified gas-phase reaction analyses are carried out. It is confirmed that the present method is practically applicable to the coupling phenomena of SWR and multiphase flow.