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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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Deep Space: The new frontier of radiation controls
In commercial nuclear power, there has always been a deliberate tension between the regulator and the utility owner. The regulator fundamentally exists to protect the worker, and the utility, to make a profit. It is a win-win balance.
From the U.S. nuclear industry has emerged a brilliantly successful occupational nuclear safety record—largely the result of an ALARA (as low as reasonably achievable) process that has driven exposure rates down to what only a decade ago would have been considered unthinkable. In the U.S. nuclear industry, the system has accomplished an excellent, nearly seamless process that succeeds to the benefit of both employee and utility owner.
Glenn A. Roth, Fatih Aydogan
Nuclear Science and Engineering | Volume 182 | Number 1 | January 2016 | Pages 71-82
Technical Paper | Special Issue on the RELAP5-3D Computer Code | doi.org/10.13182/NSE14-149
Articles are hosted by Taylor and Francis Online.
The RELAP5-3D code is used to analyze nuclear reactor systems during steady-state and transient operations. Reactor transients that result in significant two-phase flow conditions and phase change, such as reflood scenarios, loss-of-coolant accidents, and others, can tax the current capabilities of the code to model the flow fields. Current codes, such as RELAP5-3D, RELAP-7, and TRACE, have mass, momentum, and energy governing equations for only two fields (liquid and vapor). The representation of two-phase flow phenomena is improved by increasing the number of fields. Therefore, governing equations based on six fields (liquid, vapor, small bubble, large bubble, small droplet, and large droplet) are derived in this paper for implementation in RELAP5-3D.
