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Robotics & Remote Systems
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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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.
Hisashi Hishida, Tamotsu Sekiya
Nuclear Science and Engineering | Volume 47 | Number 3 | March 1972 | Pages 319-328
Technical Paper | doi.org/10.13182/NSE72-A22418
Articles are hosted by Taylor and Francis Online.
A heterogeneous method of calculating time-dependent reactor core characteristics, such as the time variation in thermal-neutron flux distribution and the reactivity change during fuel and poison burnup, is derived. The lattice consists of an infinite number of similar square zones closely connected to one another. In each zone, identical fuel rods are arranged in a regular lattice with a burnable poison rod of the same geometric dimensions as a fuel rod at the center. Some numerical examples, utilizing the equations derived finally, give the time variation in poison concentration and k∞(t) for a zone showing the heterogeneity effect associated with a burnable poison rod. Since the machine time required to compute the time variation of such core characteristics through fuel life of 11,000 EFPH as shown in the examples is <25 sec on the IBM 360/75 per case, the method may be applied to the preliminary survey calculation for the time-dependent heterogeneous core characteristics of a square lattice including burnable poison rods as well as to more general time-dependent problems related to such lattices.