THERMAL SCIENCE

International Scientific Journal

EXPERIMENTAL AND NUMERICAL INVESTIGATION OF COOLANT MIXING IN A MODEL OF REACTOR PRESSURE VESSEL DOWN-COMER AND IN COLD LEG INLETS

ABSTRACT
Thermal fatigue and pressurized thermal shock phenomena are the main problems for the reactor pressure vessel and the T-junctions both of them depend on the mixing of the coolant. The mixing process, flow and temperature distribution has been investigated experimentally using particle image velocimetry, laser induced fluorescence, and simulated by CFD tools. The obtained results showed that the ratio of flow rate between the main pipe and the branch pipe has a big influence on the mixing process. The particle image velocimetry/planar laser-induced fluorescence measurements technologies proved to be suitable for the investigation of turbulent mixing in the complicated flow system: both velocity and temperature distribution are important parameters in the determination of thermal fatigue and pressurized thermal shock. Results of the applied these techniques showed that both of them can be used as a good provider for data base and to validate CFD results.
KEYWORDS
PAPER SUBMITTED: 2014-09-15
PAPER REVISED: 2015-04-07
PAPER ACCEPTED: 2015-04-25
PUBLISHED ONLINE: 2015-09-06
DOI REFERENCE: https://doi.org/10.2298/TSCI140915121H
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2017, VOLUME 21, ISSUE 3, PAGES [1491 - 1502]
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© 2017 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence