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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.”
YuGwon Jo, Bumhee Cho, Nam Zin Cho
Nuclear Science and Engineering | Volume 183 | Number 2 | June 2016 | Pages 229-246
Technical Paper | doi.org/10.13182/NSE15-100
Articles are hosted by Taylor and Francis Online.
The continuous-energy Monte Carlo (MC) method is gaining attention not only for nuclear reactor statics but also for transient analysis, as computing power increases with the use of massive parallel computers. This paper presents a practical and accurate MC transient analysis method for heterogeneous, continuous-energy reactor transient problems, based on the predictor-corrector quasi-static (PCQS) method. The transient fixed-source problem of the PCQS method is solved by MC calculation with fission source iteration, where the partial current-based coarse-mesh finite difference (p-CMFD) method is used both to accelerate the convergence of the fission source distributions and to diagnose whether the fission source iteration diverges because of too large a macro-time-step size used for a positive reactivity insertion. To improve the convergence of the fission source iteration, exponential transformation is also applied. In addition, the variances of MC tallies can be reduced by increasing the number of active fission source iterations. For method and code verification, the PCQS method for the MC calculation with fission source iteration is compared with the implicit Euler method for a method-of-characteristics calculation on a two-dimensional TWIGL problem. For both multigroup energy and continuous-energy three-dimensional test problems, the proposed method efficiently reduces computing time with a large macro-time-step size, while the accuracy of the solutions is maintained, compared with those calculated with smaller macro-time-step sizes.