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2024 ANS Annual Conference
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Las Vegas, NV|Mandalay Bay Resort and Casino
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Nicholas Tsoulfanidis—ANS member since 1969
We welcome ANS members who have careered in the community to submit their own Nuclear Legacy stories, so that the personal history of nuclear power can be captured. For information on submitting your stories, contact nucnews@ans.org.
As an undergraduate I studied physics at the University of Athens. I entered the university in 1955 after successfully passing a national exam (came up fourth in a field of about 700 candidates). Upon graduation and finishing my mandatory two-year military service, the plan was to teach physics either in a public high school or as a tutor for a private for-profit institution, preparing high school students for the national exam.
Zeyun Wu, Won Sik Yang, Shanbin Shi, Mamoru Ishii
Nuclear Technology | Volume 193 | Number 3 | March 2016 | Pages 364-374
Technical Paper | doi.org/10.13182/NT15-58
Articles are hosted by Taylor and Francis Online.
This paper presents the core design and performance characteristics of the Novel Modular Reactor (NMR-50), a 50-MW(electric) small modular reactor. NMR-50 is a boiling water reactor with natural-circulation cooling and two layers of passive safety systems that enable the reactor to withstand prolonged station blackout and loss of ultimate heat sink accidents. The main goal in the core design is to achieve a long-life core (~10 years) without refueling for deployment in remote sites. Through assembly design studies with the CASMO-4 lattice code and coupled neutronics and thermal-hydraulic core analyses with the PARCS and RELAP5 codes, a preliminary NMR-50 core design has been developed to meet the 10-year cycle length with an average fuel enrichment of 4.75 wt% and a maximum enrichment of 5.0 wt%. The calculated fuel temperature coefficient and coolant void coefficient provide adequate negative reactivity feedbacks. The maximum fuel linear power density throughout the 10-year burn cycle is 18.7 kW/m, and the minimum critical power ratio is 2.07, both of which meet the selected design limits with significant margins. Preliminary safety analyses using the RELAP5 code show that the core will remain covered during the entire transient procedure of two design-basis loss-of-coolant accidents. These results indicate that the targeted 10-year cycle length is achievable while satisfying the operation and safety-related design criteria with sufficient margins.