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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.”
M. opi
Nuclear Science and Engineering | Volume 49 | Number 3 | November 1972 | Pages 370-376
Technical Note | doi.org/10.13182/NSE72-A22549
Articles are hosted by Taylor and Francis Online.
A new approach to the determination of average neutron transport properties of regular lattices is presented in a form amenable to any desired order of approximation. It is based on the time dependent one group integro-differential transport equation in which the cross sections are expanded in Fourier series corresponding to the periodicity of the lattice. The integral transform method yields in this case the Fourier series also for the neutron density, the zero’th term of which is separated out as the average over the lattice. The remaining Fourier coefficients are solved by a method analogous to the collision probability method and expressed in terms of the angular moments of the average neutron density. An approximate integral transform of the transport equation for the average neutron angular density is obtained that contains through its effective scattering integral the effects of the anisotropy and of the heterogeneity of the lattice. The method is applied to the problem of anisotropic diffusion constants in lattices containing voids, in particular, the diffusion constant parallel to empty channels at large channel radia is resolved. As an example, the simultaneous determination of the disadvantage factor and the anisotropic diffusion constant is also presented.