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Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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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.
Gen-Shun Chen, John M. Christenson, Dow-Yung Yang
Nuclear Science and Engineering | Volume 111 | Number 3 | July 1992 | Pages 279-293
Technical Paper | doi.org/10.13182/NSE92-A23941
Articles are hosted by Taylor and Francis Online.
The alternating direction implicit (ADI) method has been widely used to obtain numerical solutions of the two-dimensional, time-dependent, multigroup neutron diffusion equations. However, the conventional ADI method is unstable for heterogeneous problems unless extremely small time steps are used. Recently, the suitability of the ADI method for parallel computation has been noted since it is based on the solution of a system of independent block-tridiagonal matrix equations that can be solved in parallel. More precisely, on a computer with p processors, p members of the tridiagonal system can be solved in parallel using the well-known Gaussian elimination algorithm. By improving the stability of the ADI method, the method becomes extremely attractive for parallel computer applications. A mixed implicit-explicit three-level ADI method for the solution of the two-dimensional multigroup diffusion equations is introduced. Mixed implicit-explicit methods are usually more effective than purely explicit or implicit procedures for the solution of stiff equations and, for the type of problem considered, lead to a demonstrated stability improvement over the conventional ADI method. Numerical studies using the MADIprogram, which implements the three-level ADI method, show that by using the same time-step size, the method obtains results that are almost as accurate as those of the TWIGL program in about one-third to one-fourth the computational time for both homogeneous and heterogeneous two-group problems.