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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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General Kenneth Nichols and the Manhattan Project
Nichols
The Oak Ridger has published the latest in a series of articles about General Kenneth D. Nichols, the Manhattan Project, and the 1954 Atomic Energy Act. The series has been produced by Nichols’ grandniece Barbara Rogers Scollin and Oak Ridge (Tenn.) city historian David Ray Smith. Gen. Nichols (1907–2000) was the district engineer for the Manhattan Engineer District during the Manhattan Project.
As Smith and Scollin explain, Nichols “had supervision of the research and development connected with, and the design, construction, and operation of, all plants required to produce plutonium-239 and uranium-235, including the construction of the towns of Oak Ridge, Tennessee, and Richland, Washington. The responsibility of his position was massive as he oversaw a workforce of both military and civilian personnel of approximately 125,000; his Oak Ridge office became the center of the wartime atomic energy’s activities.”
Reuben T. Sorensen, John C. Lee
Nuclear Science and Engineering | Volume 158 | Number 3 | March 2008 | Pages 213-230
Technical Paper | doi.org/10.13182/NSE08-A2749
Articles are hosted by Taylor and Francis Online.
We have developed a light water reactor (LWR) equilibrium cycle search algorithm that is similar to the REBUS-3 fast reactor methodology but with depletion capabilities typically employed for LWR analysis. Our LWR methodology projects the original coupled nonlinear isotopic balance equations to a series of equations that are piecewise linear in time. Iterations are performed on microscopic reaction rates until the linearized isotopic balance equations yield an ultimate equilibrium state. We further reduce the computational burden associated with LWR analysis by approximating global depletion calculations with assembly-level, collision probability calculations performed by the CASMO-3 code. We demonstrate the benefits of our equilibrium cycle methodology by calculating the true equilibrium Pu inventory of two configurations: a heterogeneous assembly configuration that contains both low enriched UO2 and mixed oxide (MOX) fuel pins and a homogeneous configuration comprising a 2 × 2 colorset arrangement of MOX and low enriched UO2 assemblies. For each configuration our methodology yields a true equilibrium Pu inventory with only 12 CASMO-3 lattice physics calculations. As a validation, an inventory extrapolation technique is used to arrive at a quasi-equilibrium cycle for both LWR configurations. The extrapolated technique yields a similar Pu inventory and isotopic composition but requires 65 lattice physics calculations.