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The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
2021 Student Conference
April 8–10, 2021
North Carolina State University|Raleigh Marriott City Center
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ANS Board of Directors votes to retire outdated position statements
The American Nuclear Society’s Board of Directors on November 19 voted to retire several outdated position statements, as requested by the Public Policy Committee. Among them are Position Statements #37 and #63, dating from 2010, which have been retired for lacking policy recommendations and for being redundant, as other position statements exist with language that better articulates the Society’s stance on those topics.
Apoorva V. Rudra, Dinesh V. Kalaga, Masahiro Kawaji
Nuclear Science and Engineering | Volume 193 | Number 10 | October 2019 | Pages 1147-1159
Technical Paper | dx.doi.org/10.1080/00295639.2019.1595311
Articles are hosted by Taylor and Francis Online.
In order to investigate air-ingress phenomena in a gas-cooled very high temperature reactor (VHTR), natural circulation experiments have been conducted in a helium flow loop after the injection of nitrogen into the lower plenum. A pair of helium analyzers were used to measure the nitrogen and helium concentrations in the lower plenum and upper plenum. The changes in the nitrogen concentration in the upper plenum were used to calculate the time required for the transport of nitrogen from the lower plenum to upper plenum through a riser flow channel made of graphite. The effect of system temperature and pressure on the rate of nitrogen transport has been studied extensively. Furthermore, a close examination of the graphite flow channel wall temperatures at different elevations showed small but sudden drops indicating the arrival of nitrogen at each elevation. From these data, the upward transport of nitrogen injected into the lower plenum under natural circulation conditions could be quantitatively investigated. The experimental findings indicate that the driving mechanisms for air transport through the reactor core of VHTR would result from both molecular diffusion and natural circulation. At low graphite temperatures in the riser, molecular diffusion is the dominating mechanism; however, as the riser temperature increases, natural circulation becomes dominant and the rate of nitrogen transport increases. Further, the time constants for these mechanisms have been calculated using a simplified species transport equation.