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Division Spotlight
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
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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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.
Tunc Aldemir, Steven A. Arndt, Don. W. Miller
Nuclear Technology | Volume 76 | Number 2 | February 1987 | Pages 248-259
Technical Paper | Technique | doi.org/10.13182/NT87-A33879
Articles are hosted by Taylor and Francis Online.
Ionization chambers (ICs) are used in reactor protection instrument channels for monitoring neutron flux levels. These neutron sensors may degrade during the operation of the reactor through a change in their fill-gas characteristics. The comparison of the simulated and measured transient IC response to bias voltage perturbations can lead to the identification of these mechanisms. Once the mechanisms are identified, their impact on instrument channel response can be assessed by parametric studies. The charge transport model for such an identification and assessment process consists of three coupled nonlinear parabolic differential equations. The initial conditions for these equations are found by solving for the steady-state charge distribution in the IC fill gas prior to bias voltage perturbation. The space-time charge distribution in the IC is determined by a fully explicit-semi-implicit numerical scheme. The model is implemented to determine the transient response of a N2- and a xenon-filled IC to a 500- V bias voltage perturbation. In this implementation, good agreement is observed between the predicted and measured responses, with substantial improvement over the previously proposed models. The comparison of the numerical scheme to the interactive continuous system modeling program technique used in the previous studies indicates a twentyfold reduction in the number of time steps required for the simulation of a 5-ms transient. The model is also capable of quantifying the effect of fill-gas impurities on the transient IC response.
