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Division Spotlight
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.
Meeting Spotlight
2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
Standards Program
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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Latest News
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.
Bernard I. Spinrad, James S. Sterbentz
Nuclear Science and Engineering | Volume 90 | Number 4 | August 1985 | Pages 431-441
Technical Paper | doi.org/10.13182/NSE85-A18491
Articles are hosted by Taylor and Francis Online.
The Wigner-Seitz cell problem is treated by integral transport theory as a superposition of black boundary problems using the volume source and sources equivalent to the two lowest order angular components of the reentrant flux. This treatment sheds light on the convergence properties of iterative integral transport solution methods. The outgoing flux is required to have the lowest order components equal and opposite to those of the reentrant flux. Sample problems with this P11 boundary condition give good results. A new approximation to neutron transport theory is also reported. This approximation does not rely on expansion or approximation of the angular flux distribution, but rather on approximating the integral transport kernel by a sum of diffusionlike kernels that preserve spatial moments of the kernel. This might permit transport problems to be treated as a set of coupled diffusion problems in any geometry.