Chen, L.W. and Zhang, Y. (2015) Experimental observation of the nonlinear coupling of flame flow and acoustic wave. Flow Measurement and Instrumentation, 46 (Part A). 12 - 17. ISSN 0955-5986
Abstract
This is an experimental investigation to study the nonlinear coupling characteristics of a propane/air flame with acoustic standing waves, using chemiluminescence emission and phase-locked PIV measurements. A variety of coupling modes are observed for the excitation source with combustion instability oscillations and its harmonics and sub-harmonics. The frequency analysis shows that flame/acoustic coupling behaviour results in complex nonlinear coupling. The coupling behaviour is weak at lower excitation intensities (0.3V). At a voltage amplitude of 2V, the results show that the excitation frequency (f<inf>e</inf>) is only coupled with the sub-harmonic frequency (f<inf>e</inf>/5) for the premixed flame. However, for the diffusion flame, more complex frequency components are observed, which exhibit relationships of f<inf>e</inf>±f<inf>f</inf> and f<inf>e</inf>±f<inf>e</inf>/5. At a voltage amplitude of 13.7V, the sub-harmonic frequencies (2f<inf>e</inf>/5 and 3f<inf>e</inf>/5) and the premixed flame buoyancy oscillations (f<inf>f</inf>) are increased. PIV measurements provide detailed flow velocity vector fields in an acoustically excited tube for different phase angles and the effect on the flames at different equivalence ratios, which increases the understanding of flame oscillation behaviour. It is found that all of the nonlinear phenomena that are observed occur because of the coupling between buoyant and acoustic excitation and create complex nonlinear frequency couplings.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2015 Elsevier. This is an author produced version of a paper subsequently published in Flow Measurement and Instrumentation. Uploaded in accordance with the publisher's self-archiving policy. Article available under the terms of the CC-BY-NC-ND licence (https://creativecommons.org/licenses/by-nc-nd/4.0/) |
Keywords: | Flame/acoustic wave interaction; Standing wave; Nonlinear coupling; PIV |
Dates: |
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Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > Faculty of Engineering (Sheffield) > Department of Mechanical Engineering (Sheffield) |
Depositing User: | Symplectic Sheffield |
Date Deposited: | 14 Oct 2015 16:54 |
Last Modified: | 19 Sep 2017 09:31 |
Published Version: | https://dx.doi.org/10.1016/j.flowmeasinst.2015.09.... |
Status: | Published |
Publisher: | Elsevier |
Refereed: | Yes |
Identification Number: | 10.1016/j.flowmeasinst.2015.09.001 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:90867 |