Proceedings of the Korean Nuclear Society Conference (한국원자력학회:학술대회논문집)
- 1996.11a
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- Pages.328-333
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- 1996
Determination of Hot Leg Recirculation Switchover Time to Prevent Boron Precipitation during Post-LOCA LTC for ULCHIN l&2
- Park, Han-Rim (Korea Atomic Energy Research Institute) ;
- Ban, Chang-Hwan (Korea Atomic Energy Research Institute) ;
- Jeong, Jae-Hoon (Korea Atomic Energy Research Institute) ;
- Hwang, Sun-Tack (Korea Atomic Energy Research Institute) ;
- Chang, Byong-Hoon (Junior College of Inchon)
- Published : 1996.11.01
Abstract
Boric acid concentrations of the refueling water storage tank (RWST) and the accumulators for Ulchin 1&2 (UCN 1&2) are increased to meet the post loss of coolant accident (post-LOCA) shutdown requirement for the extended fuel cycles from 12 months to 18 months. To maintain long term cooling (LTC) capability following a LOCA, the switchover tine is examined using BORON code to prevent the boron precipitation in the reactor core with the increased boron concentrations. The analysis results show that, at 8 hours after the initiation of LOCA. the emergency core noting system (ECCS) should be manually realigned to the simultaneous recirculation mode from the cold leg recirculation mode.
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