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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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2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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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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Smarter waste strategies: Helping deliver on the promise of advanced nuclear
At COP28, held in Dubai in 2023, a clear consensus emerged: Nuclear energy must be a cornerstone of the global clean energy transition. With electricity demand projected to soar as we decarbonize not just power but also industry, transport, and heat, the case for new nuclear is compelling. More than 20 countries committed to tripling global nuclear capacity by 2050. In the United States alone, the Department of Energy forecasts that the country’s current nuclear capacity could more than triple, adding 200 GW of new nuclear to the existing 95 GW by mid-century.
Carol Braester, Roger Thunvik
Nuclear Technology | Volume 79 | Number 3 | December 1987 | Pages 371-376
Technical Paper | Heat Transfer and Fluid Flow | doi.org/10.13182/NT87-A34026
Articles are hosted by Taylor and Francis Online.
An analysis of the confidence of flow solutions for stochastically generated hard rock formations study was carried out with the aid of a simplified synthetic model. The formation was conceptualized as a fracture network with a known geometric structure intersecting an impervious mass rock while fracture permeability was considered a stochastic process. Safety analysis of radioactive waste repositories includes prediction of travel times of possibly contaminated water particles from the repository to the biosphere. While such calculations require that rock properties, such as permeability, be known over the entire flow domain, only limited information is available in practice, and interpolation methods are called for. An a priori model was constructed as a first step, with fracture permeabilities generated according to a given probability distribution; this a priori model was considered the “true” formation. In a second step, a limited amount of information, similar to that obtained in reality from boreholes, was used to construct a conditioned-by-measurement model. Identical flow tests were performed on formations represented by the two models, and the flow rate ratios resulting from these tests served as the measure of confidence of the stochastically generated formation. Results with a two-dimensional flow domain and a particular data set, show uncertainty values between 46 and 61%, corresponding to borehole spacing from 10 to 100 m intersecting 11 and 2%, respectively, of the total number of fractures in the network. Results with a three-dimensional flow domain show uncertainty values between 17 and 50%, corresponding to borehole spacing from 25 to 100 m intersecting 0.2 and 0.02%, respectively, of the total number of fractures. Calculations indicate that stochastically generated formation properties may lead to nonconservative results. This suggests that overestimation methods such as using permeability values obtained from an envelope passing through the highest values should be employed in order to obtain conservative results.
