ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
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Division Spotlight
Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
Meeting Spotlight
Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
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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Latest News
Virginia utility considers SMRs
Dominion Energy Virginia has issued a request for proposals from leading nuclear companies to study the feasibility of putting a small modular reactor at its North Anna nuclear power plant.
While the utility says it is not a commitment to build an SMR at the site, the RFP is “an important first step in evaluating the technology and the North Anna site to support Dominion Energy customers’ future energy needs consistent with the company’s most recent Integrated Resource Plan.”
Nobuyuki Fujita, David A. Rice
Nuclear Technology | Volume 93 | Number 1 | January 1991 | Pages 36-46
Technical Paper | Nuclear Reactor Safety | doi.org/10.13182/NT91-A34516
Articles are hosted by Taylor and Francis Online.
The reactor coolant system (RCS) water level is reduced during each refueling at some plants. Decreasing the level below the top of the loop piping (midloop operation) may be necessary to work on unisolable RCS loop components. A loss of residual heat removal (RHR) under these conditions can be serious due to the reduced water inventory, air in the RCS, and openings in the RCS loops. Under certain conditions, a loss of RHR could lead to rapid core uncovery and potential fuel damage. Core boiling due to a loss of RHR during midloop operation has received little attention until recently. The transient involves complex phenomena induced by core boiling, such as inventory loss from RCS openings and differences between the downcomer and upper plenum water levels, with the reactor vessel acting like a manometer. These phenomena cannot be easily evaluated without a versatile thermal-hydraulic computer code such as RETRAN. Yankee Atomic Electric Company’s RETRAN analysis of these phenomena reveals that the time to core uncovery is shortened by the loss of coolant through RCS openings and the manometer behavior of the reactor vessel water level. This analysis points out some limitations in applying the RETRAN code to this transient. However, the results are confirmed by a Westinghouse report issued after the completion of this analysis.