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Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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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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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.”
Gerald Houghton
Nuclear Science and Engineering | Volume 11 | Number 2 | October 1961 | Pages 121-128
Technical Paper | doi.org/10.13182/NSE61-A28056
Articles are hosted by Taylor and Francis Online.
Fundamental flux vectors have been obtained for the diffusion of bubbles in heated channels by considering bubble motion in a turbulent liquid as a Markoff process. These flux vectors lead to a nonlinear partial differential equation representing the void fraction, which has been linearized for the case of small void fractions and coupled to a similar partial differential equation governing heat flow into the liquid phase. The coupled differential equations are transformed into coupled integral equations which are solved to obtain axial void fraction and temperature distributions in a heated channel. The rate of vapor production at the wall and the rate constant for bubble growth have been calculated from experimental data on void fraction distributions at constant uniform flux. The model predicts the correct shape for the void fraction distribution curve as well as providing a plausible explanation of burnout phenomena in terms of the bubble slip velocity.
