Proceedings ArticleDOI
Performance of Core Exit Thermocouple for PWR Accident Management Action in Vessel Top Break LOCA Simulation Experiment at OECD/NEA ROSA Project
TLDR
In this paper, the results of the Large Scale Test Facility (LSTF) conducted at the Japan Atomic Energy Agency (JAEA) with a focus on core exit thermocouple (CET) performance to detect core overheat during a vessel top break loss-of-coolant accident (LOCA) simulation experiment are presented.Abstract:
Presented are experiment results of the Large Scale Test Facility (LSTF) conducted at the Japan Atomic Energy Agency (JAEA) with a focus on core exit thermocouple (CET) performance to detect core overheat during a vessel top break loss-of-coolant accident (LOCA) simulation experiment. The CET temperatures are used to start accident management (AM) action to quickly depressurize steam generator (SG) secondary sides in case of core temperature excursion. Test 6-1 is the first test of the OECD/NEA ROSA Project started in 2005, simulating withdraw of a control rod drive mechanism penetration nozzle at the vessel top head. The break size is equivalent to 1.9% cold leg break. The AM action was initiated when CET temperature rose up to 623K. There was no reflux water fallback onto the CETs during the core heat-up period. The core overheat, however, was detected with a time delay of about 230s. In addition, a large temperature discrepancy was observed between the CETs and the hottest core region. This paper clarifies the reasons of time delay and temperature discrepancy between the CETs and heated core during boil-off including three-dimensional steam flows in the core and core exit. The paper discusses applicability of the LSTF CET performance to pressurized water reactor (PWR) conditions and a possibility of alternative indicators for earlier AM action than in Test 6-1 is studied by using symptom-based plant parameters such as a reactor vessel water level detection.Copyright © 2008 by ASMEread more
Citations
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Journal ArticleDOI
Modelling guidelines for core exit temperature simulations with system codes
TL;DR: In this paper, the authors present simulations of two experiments performed at the ROSA/LSTF and PKL facilities, where experiments related to the evolution of the CET and the peak cladding temperature during transient conditions have been carried out.
Journal ArticleDOI
Accident Management Actions in an Upper-Head Small-Break Loss-of-Coolant Accident with High-Pressure Safety Injection Failed
TL;DR: In 2002, the discovery of small-break loss-of-coolant accident (SBLOCA) was reported in this paper, which is the case of the Three Mile Island accident.
Journal ArticleDOI
Reliability of Core Exit Thermocouple for Accident Management Action during SBLOCA and Abnormal Transient Tests at ROSA/LSTF
Mitsuhiro Suzuki,Hideo Nakamura +1 more
TL;DR: In this paper, experimental results on the general performances of core exit thermocouples (CETs) to detect core overheat for accident management (AM) action by using the Large Scale Test Facility (LSTF) of the ROSA Program of the Japan Atomic Energy Agency.
Core Exit temperature response during an SBLOCA event in the ASCO NPP
TL;DR: In this paper, the performance of RELAP5 and nodalization approaches for core exit temperature prediction through post-test analyses of the OECD/NEA ROSA-2 Test 3 experiment is evaluated.
References
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Detection of inadequate core cooling with core exit thermocouples: LOFT PWR experience
J.P. Adams,G.E. McCreery +1 more
TL;DR: In this article, results from four previously reported loss-of-coolant accident simulations in the Loss of Fluid Test Facility at the Idaho National Engineering Laboratory are analyzed to determine the response of the core exit thermocouples to core cladding heatup resulting from core uncovery.
Journal ArticleDOI
Post-implementation review of inadequate core cooling instrumentation
TL;DR: In this article, a review of reactor coolant inventory tracking systems (RCITS) is presented, and attention is given to operating experience, accuracy, and procedures for the detection of inadequate core cooling.
Journal ArticleDOI
Application of New Coolant Inventory Tracking Method to PWR Small Break LOCA Simulation Experiments at ROSA-IV/LSTF
TL;DR: In this article, the authors present results of an application of a new primary coolant inventory tracking method which was invented for a Westinghouse-type pressurized water reactor, to various kinds of small break loss-of-coolant accident experiments conducted at the Large-Scale Test Facility in Japan Atomic Energy Research Institute.
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