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Division members promote the advancement of mathematical and computational methods for solving problems arising in all disciplines encompassed by the Society. They place particular emphasis on numerical techniques for efficient computer applications to aid in the dissemination, integration, and proper use of computer codes, including preparation of computational benchmark and development of standards for computing practices, and to encourage the development on new computer codes and broaden their use.
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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.
F. Botta, C. Hellwig
Nuclear Science and Engineering | Volume 135 | Number 2 | June 2000 | Pages 165-176
Technical Paper | doi.org/10.13182/NSE00-A2132
Articles are hosted by Taylor and Francis Online.
Nuclear fuel can be fabricated and used in the form of microspheres (sphere-pac fuel). The heat transport mechanisms in fuel pins containing sphere-pac fuel are however very different from those in pellet pins. They are controlled not only by the thermal conductivity of fuel, cladding, and fill gas but also by particle sizes and packing density, by their state of sintering, and by radiation and gas pressure. A theoretical model is presented accounting for all these parameters, but still simple and fast enough to be implemented into a fuel pin modeling code. The basic geometrical element for this model is derived from the orthorhombic packing. For calculation of a binary package, four different radial zones within the basic element are distinguished, i.e., neck zone, gas zone, infiltrated zone, and bypass zone. The method presented here combines an analytical one-dimensional treatment with a radial heat flow relaxation procedure simulating the second (radial) dimension. Results are compared with experimental and theoretical data from the literature. With the model presented here, sophisticated modeling of sphere-pac fuel pins is possible.