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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.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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Fusion Science and Technology
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.
Cody S. Wiggins, Arturo Cabral, Lane B. Carasik
Fusion Science and Technology | Volume 77 | Number 7 | November 2021 | Pages 710-715
Technical Paper | doi.org/10.1080/15361055.2021.1898304
Articles are hosted by Taylor and Francis Online.
Development and optimization of the plasma-facing components for the fusion reactors ITER and DEMO are necessary for sufficient heat removal because of the high heat fluxes in these systems. In this work, we consider the heat transfer performance of the Cu-Cr-Zr alloy tube with a swirl (twisted tape) insert within a monoblock divertor experiencing cyclic thermal loading expected during ITER operating conditions. Thermal loading is examined up to 2000 cycles, leading to increased tube surface roughness and decreased tube thermal conductivity. A simplified model of thermal-hydraulic performance is used that accounts for forced convection in the swirled flow, conduction through the Cu-Cr-Zr tube, and tube fouling (surface roughness and thermal conductivity changes). From our work, it is found that the overall heat transfer rate of the tube is enhanced with increased thermal loading over a wide range of Reynolds numbers (i.e., flow rates). This is due to the increase of convective heat transfer from turbulence enhancement induced by increasing surface roughness. However, the increase in surface roughness also leads to an increase in pressure losses in the system, requiring increased pumping power to maintain flow rates. We consider the heat transfer rate at equivalent pumping power (quantified by the overall enhancement ratio) and find it has a complicated dependence on Reynolds number and the number of thermal loading cycles. In particular, we see that for a Reynolds number of 1 000 000, the overall enhancement ratio is decreased by up to 9% at 2000 loading cycles. Such a decrease could meaningfully impact the operations of ITER or DEMO, requiring additional pumping input to maintain sufficient heat removal. This suggests the need for further investigation of the thermal-hydraulic performance of plasma-facing components, including the full monoblock assembly, after many loading cycles.