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Title: Fast neutron fluence of yonggwang nuclear unit 1 reactor pressure vessel

Abstract

The Code of Federal Regulations, Title 10, Part 50, Appendix H, requires that the neutron dosimetry be present to monitor the reactor vessel throughout plant life. The Ex-Vessel Neutron Dosimetry System has been installed for Yonggwang Nuclear Unit 1 after complete withdrawal of all six in-vessel surveillance capsules. This system has been installed in the reactor cavity annulus in order to measure the fast neutron spectrum coming out through the reactor pressure vessel. Cycle specific neutron transport calculations were performed to obtain the energy dependent neutron flux throughout the reactor geometry including dosimetry positions. Comparisons between calculations and measurements were performed for the reaction rates of each dosimetry sensors and results show good agreements. (authors)

Authors:
; ; ;  [1];  [2]
  1. Korea Atomic Energy Research Inst., 150 Dukjin-dong, Yuseung-gu, Daejeon 305-353 (Korea, Republic of)
  2. Chungnam National Univ., 220 Gung-dong, Yuseung-gu, Daejeon 305-764 (Korea, Republic of)
Publication Date:
Research Org.:
American Nuclear Society, 555 North Kensington Avenue, La Grange Park, IL 60526 (United States)
OSTI Identifier:
22039765
Resource Type:
Conference
Resource Relation:
Conference: PHYSOR-2006: American Nuclear Society's Topical Meeting on Reactor Physics - Advances in Nuclear Analysis and Simulation, Vancouver, BC (Canada), 10-14 Sep 2006; Other Information: Country of input: France; 6 refs.
Country of Publication:
United States
Language:
English
Subject:
21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS; CAPSULES; CAVITIES; COMPARATIVE EVALUATIONS; ENERGY DEPENDENCE; EXPERIMENTAL DATA; FAST NEUTRONS; NEUTRON DOSIMETRY; NEUTRON FLUENCE; NEUTRON FLUX; NEUTRON SPECTRA; NEUTRON TRANSPORT THEORY; PRESSURE VESSELS; REACTION KINETICS; REACTOR VESSELS; YONGGWANG-1 REACTOR

Citation Formats

Yoo, C., Km, B., Chang, K., Leeand, S., and Park, J. Fast neutron fluence of yonggwang nuclear unit 1 reactor pressure vessel. United States: N. p., 2006. Web.
Yoo, C., Km, B., Chang, K., Leeand, S., & Park, J. Fast neutron fluence of yonggwang nuclear unit 1 reactor pressure vessel. United States.
Yoo, C., Km, B., Chang, K., Leeand, S., and Park, J. 2006. "Fast neutron fluence of yonggwang nuclear unit 1 reactor pressure vessel". United States. doi:.
@article{osti_22039765,
title = {Fast neutron fluence of yonggwang nuclear unit 1 reactor pressure vessel},
author = {Yoo, C. and Km, B. and Chang, K. and Leeand, S. and Park, J.},
abstractNote = {The Code of Federal Regulations, Title 10, Part 50, Appendix H, requires that the neutron dosimetry be present to monitor the reactor vessel throughout plant life. The Ex-Vessel Neutron Dosimetry System has been installed for Yonggwang Nuclear Unit 1 after complete withdrawal of all six in-vessel surveillance capsules. This system has been installed in the reactor cavity annulus in order to measure the fast neutron spectrum coming out through the reactor pressure vessel. Cycle specific neutron transport calculations were performed to obtain the energy dependent neutron flux throughout the reactor geometry including dosimetry positions. Comparisons between calculations and measurements were performed for the reaction rates of each dosimetry sensors and results show good agreements. (authors)},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2006,
month = 7
}

Conference:
Other availability
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  • In recent years, cracks were found in some boiling water reactor (BWR) pressure vessel internals. This study is to help identify locations of possible failures due to the irradiation of fast neutrons at the BWR plant in Taiwan. This study shows that with proper geometric modeling, a nodal version of the three-dimensional discrete ordinates code TORT can be used to obtain quite accurate results in BWR fast neutron fluence calculations in reasonable computing time.
  • Many neutron dosimetry issues arose in the context of life assurance/extension programs for nuclear power plants. The most important of these relates to determining the extent of reactor pressure vessel steel embrittlement caused by fast neutron leakage from the reactor core, since a key factor in reactor plant life is the service lifetime of the reactor pressure vessel. In the past, neutron dosimetry for pressure vessel surveillance purposes was carried out mainly through analyses of dosimetry sets installed in surveillance capsules. Surveillance capsule neutron dosimetry programs are limited by restrictions on the position and number of locations available and bymore » the frequency of removal of the surveillance capsules. In many cases, neutron surveillance data cannot be obtained near critical vessel locations, and dosimetry data are only obtained when the surveillance capsules are removed, so most results are averaged over several reactor operating cycles. During the past 5 years, pressure vessel surveillance dosimetry sets were deployed in the reactor cavity (annular gap) region to perform neutron dosimetry on a cycle-by-cycle basis. Solid-state track recorder (SSTR) neutron dosimeters are a key component of these reactor-cavity surveillance dosimetry sets. Measurements by SSTR neutron dosimetry have demonstrably produced high-quality results in a large number of cases, and the absolute accuracy of the technique was validated at the National Institute of Standards and Technology (NIST) through irradiations in standard neutron fields.« less
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