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Division Spotlight
Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Yoshiyuki Kataoka, Tohru Fukui, Shigeo Hatamiya, Toshitsugu Nakao, Masanori Naitoh, Isao Sumida
Nuclear Technology | Volume 99 | Number 3 | September 1992 | Pages 386-396
Technical Paper | Heat Transfer and Fluid Flow | doi.org/10.13182/NT92-A34722
Articles are hosted by Taylor and Francis Online.
To evaluate the heat removal capability of an external water wall-type containment vessel, which is a passive system for containment cooling, thermal-hydraulic behavior in the suppression and outer pools has been examined experimentally. The following results are obtained: 1. A thermal stratification boundary, which separates the pools into an upper high-temperature region and a lower low-temperature region, is observed just below the vent outlet. 2. The natural-convection heat transfer coefficients (HTCs) for the downward and upward flows that appear inside and outside the primary containment vessel wall are measured. These values can be expressed by Nu = 0.13Ra1/3. 3. The condensation HTCs in the presence of non-condensable gas, which affect heat transfer between the wet well and the outer pool, are measured along the long wall. The vertical variations of the condensation HTCs are within 10% of the averaged coefficients, and the averaged coefficients can be expressed by hm = 0.43(ma/ms)-0.8, where hm (kW/m2·K is the condensation HTC and (ma/ms) is the mass ratio of noncon-densable gas and steam. 4. The capability for decay heat removal in the external water wall-type containment vessel for a 600-MW(electric) plant is evaluated based on these results and is found to be large enough.
