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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.”
Alain Hébert, Hadrien Leroyer
Nuclear Science and Engineering | Volume 176 | Number 3 | March 2014 | Pages 312-324
Technical Paper | doi.org/10.13182/NSE13-26
Articles are hosted by Taylor and Francis Online.
We investigate the OPTEX reflector model for obtaining few-group reflector parameters consistent with a reference power distribution in the core. The reference power distribution is obtained using a 142 872-region calculation defined over a two-dimensional eighth-of-core pressurized water reactor (PWR) and performed with the method of characteristics. The OPTEX method is based on generalized perturbation theory and uses an optimization algorithm known as parametric linear complementarity pivoting. The proposed model leads to few-group diffusion coefficients or P1-weighted macroscopic total cross sections that can be used to represent the reflector in full-core calculations. These few-group parameters can be spatially heterogeneous in order to correctly represent steel baffles and thermal shields present in modern PWRs. The optimal reflector parameters are compared with those obtained with a flux-volume weighting of the reflector cross sections recovered from the reference calculation. Important improvements in full-core power distribution are observed when the optimal parameters are used.
