CSNI0070 LOFT/L8-2.

1. NAME:  LOFT/L8-2.

3. DESCRIPTION OF TEST FACILITY

The Loss-of-Fluid Test (LOFT) facility is a 50-MW(t) pressurized water reactor (PWR) system with extensive instrumentation to measure the thermal-hydraulic conditions during the experiments. The primary system operating fluid conditions of the LOFT system are typical of large [~ 3500 MW(t)], commercial PWR operations.

4. DESCRIPTION OF TEST

Experiment L8-2 is the second experiment in the LOFT Severe Core Transient Experiment Series L8, and was designed to evaluate the effect of primary coolant pump restart on core cooling when the primary coolant system (PCS) is highly voided of liquid.

The accumulator and low-pressure injection system were not allowed to inject fluid into the PCS until after core uncovery has occurred and the PCS pumps had been restarted. PCS pump restart did not produce a moderation in the core thermal transient, and Accumulator A flow was unblocked by the operator at a preselected temperature. All plant protective systems were triggered automatically shortly thereafter, followed by a rapid reflood of the PCS.

6. TYPICAL RUNNING TIME: PHENOMENA TESTED

- Donald B. Jarrell and Janice M. Divine:
Experiment Data Report for LOFT Intermediate Break Experiment L5-1
and Severe Core Transient Experiment L8-2
NUREG/CR-2398 EGG-2136 (November 1981)
- Charles L. Nalezny
Summary of Nuclear Regulatory Commission's
LOFT Program Experiments
NUREG/CR-3214 - EGG-2248 (July 1983)
- Charles L. Nalezny
Summary of Nuclear Regulatory Commission's
LOFT Program Research Findings
NUREG/CR-3005 - EGG-2231 (April 1985)
- D.L. Reeder
LOFT System and Test Description
NUREG/CR-0247 (TREE-1208) July 1978
- S.M. Modro, J. Fell
An Account of the OECD LOFT Project
OECD LOFT-T-3907 (May 1990)
- Technical Considerations for LOFT Consortium Test Plan,
Prepared for discussion by LOFT Consortium Working Group Meeting
Munich, Germany, July 15-16, 1982 (SEN/LOFT(82)6)

11. TEST DESIGNATION:  L8-2.

15. NAME AND ESTABLISHMENT OF AUTHORS

EG&G Idaho, Inc.
Idaho Falls, Idaho 83415
USA

Prepared for the
US Nuclear Regulatory Commission
Washington, D.C. 20555
USA