[KSCI] Korea Science Citation Index Service

Direct ECC Bypass Phenomena in the MIDAS Test Facility During LBLOCA Reflood Phase

B.J. Yun (Korea Atomic Energy Research Institute)
T.S. Kwon (Korea Atomic Energy Research Institute)
D.J. Euh (Korea Atomic Energy Research Institute)
I.C. Chu (Korea Atomic Energy Research Institute)
Park, W.M. (Korea Atomic Energy Research Institute)
C.H. Song (Korea Atomic Energy Research Institute)
Park, J.K. (Korea Atomic Energy Research Institute)

Publication Information

Nuclear Engineering and Technology / v.34, no.5, 2002 , pp. 421-432 More about this Journal

Abstract

As one of the advanced design features of the APR1400, direct vessel injection (DVI) system is being considered instead of conventional cold leg injection (CLI) system. It is known that the DVI system greatly enhances the reliability of the emergency core cooling (ECC) system. However, there is still a dispute on its performance in terms of water delivery to the reactor core during the reflood phase of a large-break loss-of-coolant accident (LOCA). Thus, experimental validation is under progress. In this paper, test results of direct ECC bypass performed in the steam-water test facility tailed MIDAS (Multi-dimensional Investigation in Downcomer Annulus Simulation) are presented. The test condition is determined, based on the preliminary analysis of TRAC code, by applying the ‘modified linear scaling method’with the l/4.93 length scale . From the tests, ECC direct bypass fraction, steam condensation rate and information on the flow distribution in the upper annulus downcomer region are obtained.

Keywords

DVI; reflood; direct bypass; APR-1400; modified linear scaling method;

Citations & Related Records

Reference

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