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2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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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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My Story: John L. Swanson—ANS member since 1978
. . . and in 2019, on his 90th birthday.
Swanson in 1951, the year of his college graduation . . .
My pre-college years were spent in a rural suburb of Tacoma, Wash. In 1947, I enrolled in Reed College, a small liberal arts school in Portland, Ore.; I majored in chemistry and graduated in 1951. While at Reed, I met and married a young lady with whom I would raise 3 children and spend the next 68 years of my life—almost all of them in Richland, Wash., where I still live.
I was fortunate to have a job each of my “college summers” that provided enough money to cover my college costs for the next year; I don’t think that is possible these days. My job was in the kitchen/dining hall of a salmon cannery in Alaska. Room and board were provided and the cannery was in an isolated location, so I could save almost every dollar of my salary.
Tyler Sumner, Tingzhou Fei
Nuclear Science and Engineering | Volume 196 | Number 1 | October 2022 | Pages S309-S322
Technical Paper | doi.org/10.1080/00295639.2021.2009982
Articles are hosted by Taylor and Francis Online.
The Versatile Test Reactor (VTR) is a fast spectrum test reactor currently being developed in the United States under the direction of the U.S. Department of Energy, Office of Nuclear Energy. Safety analysis of the conceptual VTR design is being performed using the SAS4A/SASSYS-1 fast reactor safety analysis code with a model representing the reactor core, primary and intermediate heat transport systems, reactor vessel auxiliary cooling system, and reactor protection system. The system’s response and safety performance has been evaluated for a wide spectrum of event initiators and accident sequences. This paper focuses on the results for several unprotected transient scenarios where the reactor protection system is assumed to fail to take any action. Even without the reactor protection system, the strong reactivity feedback response of the core reduces power to safe levels matching the available heat rejection. In the station blackout transient, the primary heat transport system is able to transition quickly and effectively to natural circulation. At the current stage of design, transient simulation results for the VTR indicate that large safety margins exist for many event initiators, including the unprotected transients presented in this paper.