TY - GEN
T1 - A separate-effect test facility for CFD-Grade measurements of the RCCS upper plenum
AU - Nguyen, Thien
AU - Petrov, Victor
AU - Manera, Annalisa
N1 - Publisher Copyright:
© Copyright (2015) by American Nuclear Society All rights reserved.
PY - 2015
Y1 - 2015
N2 - To study important 3D thermal-hydraulics effects affecting the behavior of the air-cooled Reactor Cavity Cooling System (RCCS), a separate-effects scaled facility has been built at the University of Michigan. The experimental facility is a water-based down-scaled model of the air-cooled Natural Convection Shutdown Heat Removal Test Facility (NSTF) upper plenum (Argonne National Laboratory (ANL)), and is aimed at investigating thermal stratification and mixing of multiple risers' (ducts) flows in the RCCS upper plenum. The formation of a stratified layer in the upper plenum is a reactor safety related-issue because it may inhibit the natural circulation process, and interfere with the RCCS performance. In the previous study, preliminary CFD results of the full-scale air-cooled and down-scaled water-cooled RCCS upper plenum have confirmed the scaling analysis. The current paper experimentally investigates the flow characteristics of constant-density, turbulent risers (jets) vertically discharging into the plenum. Mass flow rates of risers are adjusted to provide the uniform and/or skew velocity profiles at the outlet surfaces of risers representing the practical situations in the reactor cavity. The riser Reynolds number varies from 0.9 × 104 to 1.4 × 104. Particle image velocimetry (PIV) measurements are taken along the central plane of the risers and the central plane of a single riser (parallel to the plenum central plane). From the obtained PIV velocity fields, the flow statistics are computed. Characteristics of the risers' flows inside the plenum are investigated to provide better understanding to the behaviors of the RCCS system.
AB - To study important 3D thermal-hydraulics effects affecting the behavior of the air-cooled Reactor Cavity Cooling System (RCCS), a separate-effects scaled facility has been built at the University of Michigan. The experimental facility is a water-based down-scaled model of the air-cooled Natural Convection Shutdown Heat Removal Test Facility (NSTF) upper plenum (Argonne National Laboratory (ANL)), and is aimed at investigating thermal stratification and mixing of multiple risers' (ducts) flows in the RCCS upper plenum. The formation of a stratified layer in the upper plenum is a reactor safety related-issue because it may inhibit the natural circulation process, and interfere with the RCCS performance. In the previous study, preliminary CFD results of the full-scale air-cooled and down-scaled water-cooled RCCS upper plenum have confirmed the scaling analysis. The current paper experimentally investigates the flow characteristics of constant-density, turbulent risers (jets) vertically discharging into the plenum. Mass flow rates of risers are adjusted to provide the uniform and/or skew velocity profiles at the outlet surfaces of risers representing the practical situations in the reactor cavity. The riser Reynolds number varies from 0.9 × 104 to 1.4 × 104. Particle image velocimetry (PIV) measurements are taken along the central plane of the risers and the central plane of a single riser (parallel to the plenum central plane). From the obtained PIV velocity fields, the flow statistics are computed. Characteristics of the risers' flows inside the plenum are investigated to provide better understanding to the behaviors of the RCCS system.
KW - Hot plenum
KW - PIV
KW - Reactor cavity cooling system
KW - Riser-jet
KW - Turbulent flow
UR - http://www.scopus.com/inward/record.url?scp=84962642724&partnerID=8YFLogxK
M3 - Conference contribution
AN - SCOPUS:84962642724
T3 - International Topical Meeting on Nuclear Reactor Thermal Hydraulics 2015, NURETH 2015
SP - 1601
EP - 1614
BT - International Topical Meeting on Nuclear Reactor Thermal Hydraulics 2015, NURETH 2015
PB - American Nuclear Society
T2 - 16th International Topical Meeting on Nuclear Reactor Thermal Hydraulics, NURETH 2015
Y2 - 30 August 2015 through 4 September 2015
ER -