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Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
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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Colin Judge: Testing structural materials in Idaho’s newest hot cell facility
Idaho National Laboratory’s newest facility—the Sample Preparation Laboratory (SPL)—sits across the road from the Hot Fuel Examination Facility (HFEF), which started operating in 1975. SPL will host the first new hot cells at INL’s Materials and Fuels Complex (MFC) in 50 years, giving INL researchers and partners new flexibility to test the structural properties of irradiated materials fresh from the Advanced Test Reactor (ATR) or from a partner’s facility.
Materials meant to withstand extreme conditions in fission or fusion power plants must be tested under similar conditions and pushed past their breaking points so performance and limitations can be understood and improved. Once irradiated, materials samples can be cut down to size in SPL and packaged for testing in other facilities at INL or other national laboratories, commercial labs, or universities. But they can also be subjected to extreme thermal or corrosive conditions and mechanical testing right in SPL, explains Colin Judge, who, as INL’s division director for nuclear materials performance, oversees SPL and other facilities at the MFC.
SPL won’t go “hot” until January 2026, but Judge spoke with NN staff writer Susan Gallier about its capabilities as his team was moving instruments into the new facility.
Giovanni Maronati, Bojan Petrovic (Georgia Tech)
Proceedings | 2018 International Congress on Advances in Nuclear Power Plants (ICAPP 2018) | Charlotte, NC, April 8-11, 2018 | Pages 763-771
In this work, a thermal hydraulic analysis with RELAP5-3D/ver.40.3 of the Decay Heat Removal System (DHRS) for the Integral Inherently Safe Light Water Reactor (I2S-LWR) is discussed. The I2S-LWR is an integral reactor characterized by a high level of safety. The DHRS of the reactor is a passive safety system and it is made up of four independent trains, each composed of an Intermediate Heat Exchanger (IHX), placed in the reactor pressure vessel, an intermediate loop with pressurized water (at 70 bar) as working fluid and an Air Heat Exchanger (AHX), that rejects the residual power to the ambient air. The study consisted in modeling the I2S-LWR primary loop through the RELAP5-3D code in order to design the DHRS and analyze the shutdown transient under the Loss of Offsite Power Conditions.
The coupling system IHX-AHX has been optimized maximizing the rejected power to the ultimate heat sink under natural circulation, replacing the reactor core with two time dependent volumes with imposed temperature. The IHX has been designed limiting its dimensions to the available space in the reactor pressure vessel, while the required dimensions of the AHX, since it is not subject to space limitations, have been determined during the study.
The shutdown transient is described starting from the reactor core under nominal operating conditions and simulating the primary and secondary pump coast down with decreasing exponential functions. The analysis showed that the DHRS is capable of removing the residual power from the reactor core safely, accepting a failure of up to two trains of the DHRS. Furthermore, the presence of a fail-safe opening valve that isolates the IHX of the DHRS from the primary loop during nominal operation has been considered, showing a performance increase with the level of opening of the valve. Since the target of the DHRS is the removal of the decay power accepting the failure of one of the four trains, the AHX has been reduced in size to reach that target, in order to limit the cost of the heat exchanger.
An alternative working fluid for the intermediate loop, which consists of nanoparticles dispersed in water (nanofluid), has been evaluated. The use of nanoparticles improves the thermal properties of water through an increase in the heat transfer coefficient, but is characterized by a higher viscosity. The analysis confirmed that the bottleneck of the system is the heat transfer with ambient air in natural circulation, since the improvement in the exchanged power is not affected much by the enhancement of the thermal properties of the working fluid.
