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Division Spotlight
Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
Meeting Spotlight
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.
Lili Tong, Jie Zou, Jun Tao, Xuewu Cao
Nuclear Technology | Volume 191 | Number 1 | July 2015 | Pages 15-26
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT14-93
Articles are hosted by Taylor and Francis Online.
In the advanced passive pressurized water reactor, a passive containment cooling system (PCCS) has been adopted to cool the containment—comprising a cylindrical steel vessel—during postulated accidents, whereby the decay heat is removed through water film evaporating enhanced by air cooling outside the containment. In this study, an integrated safety analytical code is used to study the heat removal capacity of PCCS during severe accidents and its influence on severe accident management measures. The coupled analytical model includes the reactor cooling system, engineered safety features, containment system, and PCCS. Containment responses during typical design-basis accidents and integrated severe accident scenarios are calculated and validated using a design control document and probabilistic risk assessment, respectively. Four typical severe accident sequences that contribute to core damage frequency or containment high pressure are selected to evaluate the containment response. The results show that the containment pressure can be controlled at a relatively low level within 72 h with the heat removal by PCCS. Analysis of the effects of PCCS water cooling recovery during the late period of the accident sequence in severe accident management guidelines alerts as to the risk of hydrogen combustion after breaking the steam-inert atmosphere inside containment. Moreover, sensitivity analysis has been performed to study the influence of the water film coverage rate and environmental air temperature, and it shows that a decrease of the water film coverage rate and an increase of the environmental air temperature reduce the PCCS cooling capacity.