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The mission of the Decommissioning and Environmental Sciences (DES) Division is to promote the development and use of those skills and technologies associated with the use of nuclear energy and the optimal management and stewardship of the environment, sustainable development, decommissioning, remediation, reutilization, and long-term surveillance and maintenance of nuclear-related installations, and sites. The target audience for this effort is the membership of the Division, the Society, and the public at large.
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International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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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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INL’s new innovation incubator could link start-ups with an industry sponsor
Idaho National Laboratory is looking for a sponsor to invest $5 million–$10 million in a privately funded innovation incubator to support seed-stage start-ups working in nuclear energy, integrated energy systems, cybersecurity, or advanced materials. For their investment, the sponsor gets access to what INL calls “a turnkey source of cutting-edge American innovation.” Not only are technologies supported by the program “substantially de-risked” by going through technical review and development at a national laboratory, but the arrangement “adds credibility, goodwill, and visibility to the private sector sponsor’s investments,” according to INL.
T. M. Conboy, T. J. McKrell, M. S. Kazimi
Nuclear Technology | Volume 182 | Number 3 | June 2013 | Pages 259-273
Technical Paper | Fuel Cycle and Management/Thermal Hydraulics | doi.org/10.13182/NT12-58
Articles are hosted by Taylor and Francis Online.
In order to significantly increase the power density of light water reactors (LWRs), the authors propose the helical-cruciform (HC) fuel rod assembly as an alternative to traditional fuel geometry. The HC fuel rod assembly is a self-supporting nuclear fuel configuration consisting of four-petalled, axially twisted fuel rods closely packed against one another in a square array. Within the LWR core, HC fuel would possess several advantages over traditional fuel, potentially allowing for operation at a higher power density. Chief among these advantages are a larger surface-to-volume ratio, improved radial mixing characteristics of the coolant, and a shorter radial heat conduction path in the fuel pellet. In adapting helical rod geometry to the LWR core, the authors identified a shortage of correlations for fluid flow in twisted geometry flow channels, causing uncertainty in modeling studies. This gap was addressed by constructing an experimental facility for the measurement of hydraulic resistance and assembly mixing within a mock bundle of HC fuel rods. The rods were manufactured and tested in 4 × 4 square arrays at twist pitches of 200, 100, and 50 cm. Hydraulic resistance was evaluated by measuring frictional pressure drop over a 1-m length of the assembly. Results showed a higher pressure drop for the HC rods in comparison to bare cylindrical rods with no spacers, at a given mass flux, but no apparent dependency on twist pitch. However, data indicated that the HC-rod effective hydraulic diameter was only 90% of the expected value given its wetted perimeter and flow area, suggesting a shift from the traditional definition of Dh for this unique shape. Mixing tests used the technique of a hot water tracer injection into the central subchannel of the assembly of room-temperature water. Downstream temperature measurements were used to judge the rate of lateral cross flow within the HC rod bundle. Over 300 tests were analyzed, yielding a best-fit correlation for use with any twist pitch, rod length, or coolant mass flux. Compared to a traditional rod bundle, this correlation implies an enhancement in the intensity of turbulent interchange of 40% brought about by the HC geometry and a 1.6% forced diversion of axial flow per subchannel, per quarter-turn along the rod length. The correlations for hydraulics and cross-flow mixing presented here should reduce the uncertainty in future analysis of this fuel type for high-power-density LWRs.
