Abstract
In this study, the flow characteristics of a single isothermal jet discharging into the upper plenum of a 1/16th scaled facility of high temperature gas-cooled reactors was experimentally investigated. Time-resolved particle image velocimetry (TR-PIV) measurements were performed in the central plane of the jet flow and the upper plenum for various jet Reynolds numbers ranging from 3, 413 to 12, 819. From the acquired TR-PIV velocity snapshots, statistical characteristics of the jet flows such as the mean velocity, root-mean-square fluctuating velocity, and Reynolds stress were computed and presented. Furthermore, two-point velocity cross-correlations, spectral analysis, and squared coherent functions were performed on the TR-PIV velocity vector fields. The estimated integral length scales were found to linearly increase downstream and along the jet shear layers in the axial direction, while the squared coherent functions remained close to unity for small spatial separations and lower frequencies up to 50 Hz for points at y/D j =1 and 2.
Original language | English |
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Pages (from-to) | 113-129 |
Number of pages | 17 |
Journal | International Journal of Heat and Fluid Flow |
Volume | 76 |
DOIs | |
State | Published - Apr 2019 |
Externally published | Yes |
Funding
The first author, Anas Alwafi, would like to acknowledge the scholarship from the King Abdulaziz City for Science and Technology ( KACST ), Saudi Arabia.
Keywords
- Isothermal impinging jet
- Time-resolved particle image velocimetry
- Two-point cross-correlation
- Upper plenum