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Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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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.
Shikha A. Ebrahim, Nurali Virani, Shi Chang, Fan-Bill Cheung (Penn State)
Proceedings | 2018 International Congress on Advances in Nuclear Power Plants (ICAPP 2018) | Charlotte, NC, April 8-11, 2018 | Pages 387-396
An advance image processing technique is developed to quantitatively characterize the liquid-vapor interfacial waves, vapor layer thickness, minimum film boiling temperature (Tmin), quenching temperature (TQ), quenching time, and quench front velocity in the film boiling heat transfer regime. A facility was constructed with the purpose of performing high-temperature quenching of a simulated fuel rod in a near-saturated/subcooled water pool at atmospheric pressure. Inconel-600 tubular test sample with an outer diameter of 9.5 mm and a length of 25 cm was used. The test section has an embedded thermocouple that is connected to a data acquisition system for recording the temperature transients during quenching. An inverse heat conduction code was used to calculate the surface temperature and the corresponding heat flux. The latter was used to determine Tmin, which represents the minimum heat flux point on the boiling curve.
When a heated test section at a sufficiently high temperature plunges in a saturated or subcooled pool, a stable and continuous vapor layer is formed around it, preventing the liquid from being in a direct contact with the heated surface during film boiling. As the surface temperature of the rod gradually decreased, the vapor film starts to collapse at Tmin. Subsequently, the rod temperature dropped dramatically as the regime of heat transfer changed from transition boiling to nucleate boiling. Visualization of the boiling behavior was captured by a high-speed camera at a frame rate of 750 frames per second (fps) from which the vapor film thickness and the behavior of the liquid-vapor interface in the film boiling regime were analyzed frame by frame. The vapor-liquid interfacial waves as well as their temporal evolution are visualized for a range of wall superheat and various degrees of liquid subcooling. The thermocouple data and the taken videos are synchronized to couple the behavior of the vapor layer with the thermal behavior of the heated rod. Through the intensive image analyses, it was concluded that the vapor film thickness decreases contributing to a higher Tmin. Additionally, more oscillations of the vapor-liquid interface were found in the case of near-saturated pool. The quench front speed was observed to be constant for each subcooling.
