Proceedings of the Korean Nuclear Society Conference (한국원자력학회:학술대회논문집)
- 1997.10a
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- Pages.611-616
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- 1997
A Study on Thimble Plug Removal for PWR Plants
- Song, Dong-Soo (Korea Electric Power Research Institute) ;
- Lee, Chang-Sup (Korea Electric Power Research Institute) ;
- Lee, Jae-Yong (Korea Electric Power Research Institute) ;
- Jun, Hwang-Yong (Korea Electric Power Research Institute)
- Published : 1997.10.01
Abstract
The thermal-hydraulic effects of removing the RCC guide thimble plugs are evaluated for 8 Westinghouse type PWR plants in Korea as a part of feasibility study: core outlet loss coefficient, thimble bypass flow, and best estimate flow. It is resulted that the best estimate thimble bypass flow increases about by 2% and the best estimate flow increases approximately by 1.2%. The resulting DNBR penalties can be covered with the current DNBR margin. Accident analyses are also investigated that the dropped rod transient is shown to be limiting and relatively sensitive to bypass flow variation.
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