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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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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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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Proving DRACO will deliver
The United States is now closer than it has been in over five decades to launching the first nuclear thermal rocket into space, thanks to DRACO—the Demonstration Rocket for Agile Cislunar Orbit.
T. H. Newton, Jr., M. S. Kazimi, E. E. Pilat
Nuclear Science and Engineering | Volume 157 | Number 3 | November 2007 | Pages 264-279
Technical Paper | doi.org/10.13182/NSE07-A2727
Articles are hosted by Taylor and Francis Online.
The Massachusetts Institute of Technology (MIT) Reactor II (MITR-II) is a 5-MW research reactor presently fueled with highly enriched uranium (HEU) in uranium-aluminum plate-type elements. A low-enriched uranium (LEU)-fueled core has been designed using 20% enriched monolithic uranium-molybdenum fuel that maintains high experimental neutron flux and increases flexibility in meeting the needs of experiments. The configuration of the new plate fuel elements was selected using a full-core MCNP model, with which different in-core materials were evaluated to optimize the neutron fluxes, reactivity, and experimental neutron spectrum. In-core materials were chosen to meet experimental flux level and spectrum needs. Of the designs evaluated, the most promising consisted of half-width fuel elements with nine U-7Mo LEU fuel plates.Results from the MCNP/ORIGEN linkage code MCODE depletion calculations showed that the refueling interval of the chosen LEU core would be twice as long as the HEU core at the same power level. Thermal-hydraulic analysis using the MULtiCHannel analysis code II (MULCH-II) indicated that the peak channel will remain below the onset of nucleate boiling under normal and loss-of-flow conditions. A thermal-hydraulic evaluation of the limiting channel using point kinetics showed that the LEU core could withstand a step reactivity insertion of 3.92 $, increasing by 60% the allowable reactivity for an in-core experiment. Finally, preliminary analyses show that it may be feasible to use the proposed design to double the core power, if the fuel cycle length is to be kept at its present length.