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Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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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Nuclear Science and Engineering
October 2024
Nuclear Technology
Fusion Science and Technology
August 2024
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.
Gregory A. Moses
Nuclear Science and Engineering | Volume 64 | Number 1 | September 1977 | Pages 49-63
Technical Paper | doi.org/10.13182/NSE77-A27076
Articles are hosted by Taylor and Francis Online.
Laser fusion hydrodynamics calculations include both the solution of the plasma hydrodynamics equations and transport equations for various nonthermal particles. The solution of the hydrodynamics equations is usually a combination of an explicit technique for the hyperbolic equation-of-motion and an implicit method for parabolic temperature equations. Transport equations are solved using fully implicit techniques to allow their time step to be as large as the time step used in the solution of the hydrodynamics equations. Multigroup flux-limited diffusion theory is often used to model the time-dependent transport problem. In this method, the diffusion coefficient is “adjusted” to provide a physically plausible result in the free streaming limit. The energy dependence of the distribution function is modeled using multigroup theory. Another method of solving the transport problem, time-dependent particle tracking, approximates the trajectory of the charged particles as straight lines, from creation to thermalization. This simple method accurately describes the slowing down of thermonuclear reaction products, while the flux-limited diffusion technique is more applicable to the transport of electrons and photons.