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The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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.
Wei Ji, William R. Martin
Nuclear Science and Engineering | Volume 169 | Number 1 | September 2011 | Pages 19-39
Technical Paper | doi.org/10.13182/NSE10-73
Articles are hosted by Taylor and Francis Online.
In this paper the chord method is applied to the computation of Dancoff factors for doubly heterogeneous stochastic media, characteristic of prismatic and pebble bed designs of the Very High Temperature Gas-Cooled Reactor (VHTR), where TRISO fuel particles are randomly distributed in fuel compacts or fuel pebbles that are arranged in a full core configuration. Previous work has shown that a chord length probability distribution function (PDF) can be determined analytically or empirically and used to model VHTR lattices with excellent results. The key observation is that once the chord length PDF is known, Dancoff factors for doubly heterogeneous stochastic media can be expressed as closed-form expressions that can be evaluated analytically for infinite and finite media and semianalytically for a collection of finite media.Based on the assumption that the chord length PDF in the moderator region between two fuel kernels in a VHTR compact or pebble is exponential, which was shown to be an excellent approximation in previous work, closed-form expressions for Dancoff factors are derived for a range of configurations from infinite stochastic media to finite stochastic media, including multiple finite stochastic media in a background medium (e.g., a pebble bed core). Numerical comparisons with Monte Carlo benchmark results demonstrate that the closed-form expressions for the Dancoff factors for VHTR configurations are accurate over a range of packing fractions characteristic of prismatic and pebble bed VHTRs.