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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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Penn State and Westinghouse make eVinci microreactor plan official
Penn State and Westinghouse Electric Company are working together to site a new research reactor on Penn State’s University Park, Pa., campus: Westinghouse’s eVinci, a HALEU TRISO-fueled sodium heat-pipe reactor. Penn State has announced that it submitted a letter of intent to host and operate an eVinci reactor to the Nuclear Regulatory Commission on February 28 and plans to engage with the NRC on specific siting decisions. Penn State already boasts the Breazeale reactor, which began operating in 1955 as the first licensed research reactor at a university in the United States. At 70, the Breazeale reactor is still in operation.
E. R. Sanford, H. J. Litre
Nuclear Science and Engineering | Volume 4 | Number 6 | December 1958 | Pages 713-726
doi.org/10.13182/NSE58-A15494
Articles are hosted by Taylor and Francis Online.
An experiment was conducted in a critical assembly to determine water channel power peaking in a heterogeneous, highly enriched, water-moderated reactor subassembly. In addition to horizontal profiles of power density in a plane below a bank of control rods, data were obtained on the interacting effects of the control rod channel and bottom reflector power peaks. Experimental techniques are discussed. A computation for a comparable multiregion cell was made using a few-group diffusion theory digital computer code. Comparison of the results showed that variations in fast neutron spectrum and in manner of homogenization of materials within cell regions had no appreciable effects upon the power density peak. The choice of thermal neutron spectrum is important. Agreement between all experimental values and calculations with a Maxwellian spectrum was excellent. The comparison between experiment and calculations with a hardened thermal neutron spectrum was relatively poor. The results of this investigation indicate that great care must be exercised in interpreting experimental data on power distribution, and that two-dimensional diffusion theory calculations of power density are substantially verified. The use of U235 monitor foils is recommended in order to obtain a true fission power distribution. It was found that variations in the water gap width of the order of 10% had negligible effect upon the horizontal peak-to-average power ratio in the fuel. The use of metallic control rod extensions was found to decrease the horizontal peak-to-average ratio substantially, the magnitude of the decrease verifying analytical predictions.
