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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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.
Dae-Hyun Hwang, Kyong-Won Seo, Chung-Chan Lee
Nuclear Technology | Volume 158 | Number 2 | May 2007 | Pages 219-228
Technical Paper | Nuclear Reactor Thermal Hydraulics | doi.org/10.13182/NT07-A3837
Articles are hosted by Taylor and Francis Online.
Critical heat flux (CHF) in rod bundles is a parameter of great importance for the thermal-hydraulic design and safety analysis of advanced light water reactors. An experimental investigation has been conducted for the 19-rod hexagonal test bundles with a tightly spaced nonsquare arrangement of heater rods. The parametric effects on the CHF were examined for the heated length, the unheated rod, and the nonuniform axial power shape. As a result, a pertinent CHF correlation has been developed on the basis of the bundle cross-sectional averaged conditions. The available CHF database for rod bundles with square and nonsquare rod pitches was employed for the assessment of representative CHF correlations that were applicable to the round tubes and rod bundles. The database covered a wide range of operating conditions and test bundle geometries that are applicable to advanced light water reactors. The prediction accuracy of the CHF correlations was evaluated on the basis of the local thermal-hydraulic conditions calculated by a subchannel analysis code.
