Post-Test Thermal-Hydraulic Analysis of PKL Tests F1.1 and F1.2 (NUREG/IA-0417)

On this page:

Download complete document

Publication Information

Manuscript Completed: April 2011
Date Published: October 2014

Prepared by:
J. Freixa, C. Pretel, L. Batet, F. Reventós

Institute of Energy Technologies
Department of Physics and Nuclear Engineering
Technical University of Catalonia
ETSEIB, Av. Diagonal 647, Pav. C
08028 Barcelona Spain

K. Tien, NRC Project Manager

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

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

Availability Notice


Two different post-test analyses have been performed by making use of the UPC’s model of the PKL facility. The nodalization has been developed using the RELAP5mod3.3 code and two tests of the OECD/PKL project, namely Test F1.1 and F1.2, have been simulated. For both transients, the simulations correctly reproduce the finalization of natural circulation and the beginning of the reflux condensation conditions with the consequent formation of low borated water slugs in the loop seals due to the phenomenon of boron dilution.

Test F1.1 is a Small Break LOCA in the cold leg assuming the non-availability of the LPI system and the accumulators while Test F1.2 simulates a series of steady state situations for different primary inventories in order to study the phenomenon of boron dilution as a function of the mass inventory.

Different sensitivity analyses are also reported and the nodalization of the U-tubes bundle is discussed for both scenarios. The results cover the formation of slugs in the loop seals under reflux and condensation conditions and their movement through the loop when the U-tubes are refilled and natural circulation is re-established.

Page Last Reviewed/Updated Tuesday, March 09, 2021