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Division Spotlight
Robotics & Remote Systems
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.
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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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.
Y. Zhai, C. Neumeyer, J. Dellas, N. Greenough, M. Kalish, J. Petrella, W. Que, S. Raftopoulos, and the NSTX-U Coil Test Team
Fusion Science and Technology | Volume 75 | Number 8 | November 2019 | Pages 775-785
Technical Paper | doi.org/10.1080/15361055.2019.1610314
Articles are hosted by Taylor and Francis Online.
The National Spherical Torus eXperiment Upgrade (NSTX-U) is an innovative magnetic fusion device constructed at the Princeton Plasma Physics Laboratory (PPPL). In 2016, because of the failure of the PF-1a upper divertor coil, which experienced a coolant blockage, the NSTX-U operation was suspended. A postmortem investigation indicated that an undetected gradual deterioration of coil inductance preceded the coolant blockage leading up to the operational suspension. The project team decided that all inner poiloidal field (PF) upper and lower coil pairs, denoted PF-1a, PF-1b, and PF-1c, shall be replaced with new coils of improved design and manufacture. The new prototype inner PF coils from four suppliers across the globe were evaluated at PPPL following a prototype technical evaluation procedure. Mechanical inspection and electrical testing were performed to qualify each supplier.
This paper discusses the details of the mechanical and electrical tests and measurements performed on the complete coils. The test results were used to assess quality of turn-to-turn and turn-to-ground insulations of the prototype coils. Two prototype coils were power tested at PPPL for five pulses to reach its rated current and maximum temperature following the completion of low-power electrical testing. During pulses, the conductors experience a near adiabatic temperature rise and hoop stress. Between pulses, cold water enters the inlet, and a cooling wave propagates through the coils as slugs of cold water heat up to the conductor temperature and then pass through the coil to the outlet. Results show that full power testing did not change coil electrical characteristics. Each prototype coil was then sectioned into two halves to permit examination of the internal insulation, conductor spacing, and vacuum pressure impregnation quality. The high-voltage breakdown test of sectioned coils was performed to evaluate turn and ground insulation breakdown voltage. The estimate for the production coils is based largely on the experience learned from the prototype coil program. The first production coil will be delivered to PPPL for testing by January 2020.