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Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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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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.
M. K. Moallemi, R. Viskanta
Nuclear Science and Engineering | Volume 98 | Number 3 | March 1988 | Pages 209-225
Technical Paper | doi.org/10.13182/NSE88-A22323
Articles are hosted by Taylor and Francis Online.
A model has been developed to predict the thermal hydraulics in the uncovered part of a pressurized water reactor core. The core is considered to be a heterogeneous porous medium with different permeabilities and effective thermal conductivities in the radial and axial directions. The flow in the core is modeled by the Brinkman-Forchheimer extended Darcy equations. The dependence of the thermophysical properties of the coolant (steam-hydrogen mixture) and the fuel rods with temperature is accounted for. Oxidation of the Zircaloy is also modeled, and transport of the generated hydrogen in the uncovered portion of the reactor core is considered. The effects of the thermal boundary condition at the outlet of the core (i.e., at the upper tie plate) are studied and reported. Partial blockage of the core due to the mechanical failure and/or melting of some of the fuel rods is also modeled, and its effects on the thermal hydraulics of the core are studied and discussed. Numerical simulations are reported for the Three Mile Island Unit 2 reactor conditions. The results show that the flow field in the core is affected by exothermic heat release as well as by a decrease of the coolant density due to the Zircaloy cladding oxidation. In addition, the results show that there is entrapment of the coolant from the upper plenum into the core. The partial blockage of the core was found to have a profound influence on the heatup of the core.