Abstract
High-resolution large-eddy simulations (LES) are performed for an incompressible turbulent circular jet impinging upon a vibrating heated wall supplied with a constant heat flux. The present work serves to understand the flow dynamics and thermal characteristics of a turbulent jet under highly dynamic flow and geometric conditions. The baseline circular vibrating-wall jet impingement configuration undergoes a forced vibration in the wall-normal direction at the frequency, f = 100 Hz. The jet Reynolds number is Re=DVb/ν = 23,000 and the nozzle-exit is at y/D = 2 where the wall vibrates between 0 and 0.5D with amplitude of vibration, A = 0.25D. The configuration is assembled through validation of sub-systems, in particular the method for generating the turbulent jet inflow and the baseline circular jet impingement configuration. Both time-mean and phase-averaged results are presented. The mean radial velocity increases upon positive displacement of the wall and decreases upon negative displacement but this correlation changes with increased radial distance from the stagnation point. Vortical structures are shown to play a major role in convective heat transfer even under the vibrating conditions of the impingement wall. Periodic shifts in the secondary Nusselt number peak are observed that depend upon the travelling eddy location and strength of large-eddy structures. Enhancement in heat transfer is seen in the stagnation region but this beneficial effect of vibration on heat transfer is confined to the impingement region, r/D <1.5.
Publisher Statement: NOTICE: this is the author’s version of a work that was accepted for publication in International Journal of Heat and Fluid Flow. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in International Journal of Heat and Fluid Flow, [65, (2016)] DOI: 10.1016/j.ijheatfluidflow.2016.11.006
Publisher Statement: NOTICE: this is the author’s version of a work that was accepted for publication in International Journal of Heat and Fluid Flow. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in International Journal of Heat and Fluid Flow, [65, (2016)] DOI: 10.1016/j.ijheatfluidflow.2016.11.006
© 2016, Elsevier. Licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/
| Original language | English |
|---|---|
| Pages (from-to) | 277-298 |
| Number of pages | 22 |
| Journal | International Journal of Heat and Fluid Flow |
| Volume | 65 |
| Early online date | 30 Nov 2016 |
| DOIs | |
| Publication status | Published - Jun 2017 |
Bibliographical note
NOTICE: this is the author’s version of a work that was accepted for publication in International Journal of Heat and Fluid Flow. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in International Journal of Heat and Fluid Flow, [65, (2016)] DOI: 10.1016/j.ijheatfluidflow.2016.11.006© 2016, Elsevier. Licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/