Evaluation for 4-Inch Cold Leg Top-Slot Break LOCA in ATLAS Facility with RELAP5 Mod3.3 Patch5

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Publication Information

Manuscript Completed: February 2020
Date Published: January 2021

Prepared by:
J. Kim*, K.-H. Kang*, B.-U. Bae*, Y. Park*, A. Shin**, M. Cho**

*Korea Atomic Energy Research Institute,
111, Daedeok-daero 989beon-gil, Yuseong-gu, Daejeon, Korea

**Korea Institute of Nuclear Safety
62 Gwahak-ro, Yuseong-gu, Daejeon 34142, Republic of Korea

K. Tien, NRC Project Manager

Division of Systems Analysis
Office of Nuclear Regulatory Research
U.S. Nuclear Regulatory Commission
Washington, DC 20555-0001

Prepared as part of:
The Agreement on Research Participation and Technical Exchange
Under the Thermal-Hydraulic Code Applications and Maintenance Program (CAMP)

Published by:
U.S. Nuclear Regulatory Commission
Washington, DC 20555-0001

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The present works, an ATLAS test for 4-Inch cold leg top-slot break LOCA and a simulation of this test with RELAP5 Mod3.3 Patch5, are presented and the calculation results are compared and discussed against the test data. An ATLAS model for RELAP5 was applied for steady state. And then, a transient calculation was performed with a break line model that was developed for the present work. The RELAP5 calculations show a reasonable agreement with the test data. Especially, the RELAP5 predicted repeatable loop seal clearing and reformation in the test. The loop seal clearing and reformation led no excursion in the cladding temperature in both the test and RELAP5 calculation.

Page Last Reviewed/Updated Wednesday, March 24, 2021