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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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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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Latest News
X-energy, Dow apply to build an advanced reactor project in Texas
Dow and X-energy announced today that they have submitted a construction permit application to the Nuclear Regulatory Commission for a proposed advanced nuclear project in Seadrift, Texas. The project could begin construction later this decade, but only if Dow confirms “the ability to deliver the project while achieving its financial return targets.”
M. Gentili, B. Fontaine, G. Rimpault
Nuclear Technology | Volume 192 | Number 1 | October 2015 | Pages 11-24
Technical Paper | Fission Reactors | doi.org/10.13182/NT14-123
Articles are hosted by Taylor and Francis Online.
Fast reactor designs are currently being revisited aiming at having a consolidated safety dossier. In that frame, studying any perturbation of nominal operating condition is mandatory.
Among different initiators, particular attention is being paid to reactivity insertion due to core assembly bowing and deformation and induced lattice readjustments as a consequence of events such as earthquakes.
In this study, a deterministic calculation scheme based on the mesh projection method has been used in order to evaluate the reactivity changes occurring in a deformed sodium fast reactor core.
With the microscopic cross sections calculated by ECCO, full three-dimensional core calculations are being conducted with ERANOS (DIF3D), VARIANT, and SNATCH to solve neutron transport equations in either diffusion, nodal variational, or Sn transport approximations.
A simple analytical model based on perturbation theory has been developed to identify the main phenomena leading to changes in the core reactivity. Reactivity changes induced by small deformations can be estimated as a summation of reactivity perturbations of individual subassemblies.
The results obtained with this method have been checked by comparing them to those obtained with Monte Carlo simulations. A good agreement is being found allowing the use of this method in realistic problems with significant computer resource reduction.
The different contributions to the reactivity changes confirm the results of the analytical model.
