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Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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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.
G. Marleau, A. Hebert
Nuclear Science and Engineering | Volume 111 | Number 3 | July 1992 | Pages 257-270
Technical Paper | doi.org/10.13182/NSE92-A23939
Articles are hosted by Taylor and Francis Online.
The J± technique is an approximation of the collision probability (CP) method in which a probability matrix is associated with each homogeneous region, and then, these regions are coupled using an interface current technique. The main advantages of the J± technique are its speed and the fact that the probability matrix associated with each region is completely decoupled from its environment. Previous work using the DP0 approximation of the J± technique has been carried out for cluster geometries. Here, the DP1 approximation is investigated, and in addition to the uniform angular flux contribution, linearly anisotropic contributions are also considered. For cluster geometries, this results in an approximation for the angular fluxes of the form ψ(rs,Ω) = a + b(Ω.N), where a and b are expansion coefficients to be determined, Ω is the neutron angular direction, and N is normal at surface s. A surf ace fractioning correction is also introduced to remove the diffraction effect that arises when using the J± method in two-dimensional geometries. The results obtained by means of the DPI approximation are now very close to those of the CP method.