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Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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Fusion Science and Technology
Latest News
College students help develop waste-measuring device at Hanford
A partnership between Washington River Protection Solutions (WRPS) and Washington State University has resulted in the development of a device to measure radioactive and chemical tank waste at the Hanford Site. WRPS is the contractor at Hanford for the Department of Energy’s Office of Environmental Management.
B. Zhao, S. A. Musa, S. I. Abdel-Khalik, M. Yoda
Fusion Science and Technology | Volume 72 | Number 3 | October 2017 | Pages 300-305
Technical Paper | doi.org/10.1080/15361055.2017.1333828
Articles are hosted by Taylor and Francis Online.
The leading candidate for the DEMO divertor is the helium-cooled modular divertor with multiple jets (HEMJ) design, which is to date the only design that has been experimentally shown to accommodate incident steady-state heat fluxes greater than 10 MW/m2. In the HEMJ, the divertor target plates are cooled by 25 jets of different diameters that impinge upon a curved tungsten (W)-alloy surface brazed to a hexagonal W tile. Given the difficulties in manufacturing such a complicated geometry in W and W-alloys, numerical simulations were performed to determine if simplified versions of the HEMJ design could provide similar thermal-hydraulic performance. Parametric studies were performed at fully prototypical conditions using one-way coupled thermo-mechanical and fluid dynamics simulations in ANSYS® Workbench® to determine the effect of varying the jet-to-cooled surface distance, the number, diameter, and spacing of the jet holes (the jets were all assumed to have the same diameter), and the curvature of the cooled surface on the thermal-hydraulic performance. The results for the evaluated 75 different jet array configurations suggest that similar and even superior thermal-hydraulic performance can be provided by several designs. These HEMJ variants with fewer jets and larger holes may reduce fabrication costs and improve reliability. For example, the simulations suggest that a configuration involving flat surfaces with six holes surrounding one central hole, all with a diameter of 1.18 mm at a jet-to-cooled surface distance of 1.25 mm provides a 6.6% higher average heat transfer coefficient (HTC) at a 4.8% lower pressure drop when compared with the HEMJ. The maximum temperature of the outer shell and cooled surface stress are also lower for this design. In all cases, the simulations also suggest that the jet-to-cooled surface distance decreases by approximately 0.2 mm when the temperature increases from ambient to prototypical conditions due to differential thermal expansion of the jets cartridge and the W-alloy pressure boundary.