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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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Latest News
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.
Jeremy Bittan
Nuclear Science and Engineering | Volume 194 | Number 8 | August-September 2020 | Pages 771-781
Technical Paper | doi.org/10.1080/00295639.2020.1743576
Articles are hosted by Taylor and Francis Online.
During a loss-of-coolant-accident (LOCA) transient in a pressurized water reactor (PWR), water from the primary circuit is lost at the break. PWR designs are equipped with safety systems (SS) such as safety injection or accumulators to inject water into the primary circuit and prevent the core from being degraded. Depending on the size, position, and orientation of the break, a part of the safety system injection (SSI) into the primary circuit will be lost at the break. This parameter has a significant influence on the time the core uncovers in case the SS are lost. MAAP5.04 enables users to define the part of SSI that is lost at the break. Apart from a double-ended–break LOCA transient, users struggle to define precisely the part of SSI lost at the break, but this choice can have an important impact on the transient key event times. Thanks to its detailed equations and nodalization, the reference Code for Analysis of Thermal Hydraulics during an Accident of Reactor and safety Evaluation (CATHARE) enables one to evaluate the part of SSI lost at the break. Numerous CATHARE calculations have been performed taking into account different break sizes, positions, and orientations to determine the part of SSI lost at the break in each case. A metamodel has been created from the constituted database and implemented in EDF MAAP5.04. This paper also presents the impact of these improvements on LOCA transients where SS are lost.