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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.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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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.
Allen C. Smith, James E. Blake, Michael T. Childerson, Ted R. Ohrn, Robert M. Privette
Nuclear Technology | Volume 106 | Number 2 | May 1994 | Pages 254-260
Technical Note | Heat Transfer and Fluid Flow | doi.org/10.13182/NT94-A34980
Articles are hosted by Taylor and Francis Online.
Analytical studies of the effects of power on flow instability in parallel channels with upward flow of coolant have predicted that the Ledinegg flow instability, encountered as flow is decreased for typical operating power levels, would not be experienced at low-power levels. For a system in which the flow of coolant is upward, the increased buoyancy enhances flow in the channel, so that as the void increases, the overall pressure loss decreases. Under this condition, flow instability does not occur. Testing was performed to confirm the predicted behavior and to provide data for benchmarking of computer codes used for predicting the performance of reactor fuel elements. The demand curves traced in these tests are part of the multidimensional demand surface for the test apparatus. The basic coordinates of this surface are flow rate, pressure drop, and power. A fourth significant independent variable is system pressure, so that the behavior of the system is represented by a family of Δp-flow-power surfaces for each pressure level. This testing confirmed that, at low power levels comparable to decay heat removal power, the buoyancy effects may become dominant so that the demand curve for the fuel assembly turns downward and flow instability will not occur.