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September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Remembering ANS member Gil Brown
Brown
The nuclear community is mourning the loss of Gilbert Brown, who passed away on July 11 at the age of 77 following a battle with cancer.
Brown, an American Nuclear Society Fellow and an ANS member for nearly 50 years, joined the faculty at Lowell Technological Institute—now the University of Massachusetts–Lowell—in 1973 and remained there for the rest of his career. He eventually became director of the UMass Lowell nuclear engineering program. After his retirement, he remained an emeritus professor at the university.
Sukesh Aghara, chair of the Nuclear Engineering Department Heads Organization, noted in an email to NEDHO members and others that “Gil was a relentless advocate for nuclear energy and a deeply respected member of our professional community. He was also a kind and generous friend—and one of the reasons I ended up at UMass Lowell. He served the university with great dedication. . . . Within NEDHO, Gil was a steady presence and served for many years as our treasurer. His contributions to nuclear engineering education and to this community will be dearly missed.”
Hans G. Kaper, Gary K. Leaf, Arthur J. Lindeman
Nuclear Science and Engineering | Volume 49 | Number 1 | September 1972 | Pages 27-48
Technical Paper | doi.org/10.13182/NSE72-A22525
Articles are hosted by Taylor and Francis Online.
This paper contains the results of detailed comparison studies of the efficiency of high order finite element approximations vs low order finite difference approximations, for the numerical solution of the static multigroup diffusion equation in two dimensions. The comparisons are based on the execution times for a Keff calculation with a prescribed precision for two particular computer programs— HOD (finite elements) and D ARC2D (finite differences). The calculations were performed for three different types of reactor configurations: a simple two-zone configuration with two energy groups, a multizone configuration [1000-MW(e) LMFBR mockup] with four energy groups, and a loosely coupled configuration with two energy groups. The conclusions are: 1. The use of high order approximation procedures based on finite element methods leads to substantial execution time savings and offers not just a viable alternative to the use of low order approximation procedures based on finite difference methods; it is, indeed, a significant advancement in computational capability. 2. With high order approximation procedures based on finite element methods it is possible to obtain, at reasonable cost, solutions to the multigroup diffusion equation which are sufficiently accurate that any errors can be attributed to either the diffusion theory approximation or other approximations in the reactor model, rather than to the numerical approximation procedure. 3. Solutions obtained with the finite element method provide as much accuracy in the flux inventories as in the multiplication factor.
