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Nuclear Criticality Safety
NCSD provides communication among nuclear criticality safety professionals through the development of standards, the evolution of training methods and materials, the presentation of technical data and procedures, and the creation of specialty publications. In these ways, the division furthers the exchange of technical information on nuclear criticality safety with the ultimate goal of promoting the safe handling of fissionable materials outside reactors.
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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.
J. Michael Doster, Mark A. Holmes
Nuclear Science and Engineering | Volume 124 | Number 1 | September 1996 | Pages 125-144
Technical Paper | doi.org/10.13182/NSE96-A24229
Articles are hosted by Taylor and Francis Online.
A standard model for describing time-dependent two-phase flows is the so-called six-equation or two-fluid model, where mass, energy, and momentum equations are considered for each phase. It is well known that the single-pressure form of this model can contain complex characteristics and is therefore ill posed. This ill-posedness has been blamed for numerical instabilities that have at times been observed when finite difference solutions of these equations have been attempted. One method to render the characteristics real is to include viscous terms. The numerical implications of adding viscous terms to the six-equation model are considered, and the potential impact of these implications on the stability of the finite difference solution is evaluated.