Experimental and Numerical Study of Swirling Flows and Flame Dynamics

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Abstract

The effect of swirling air on the flow dynamics was investigated for the cold non-reacting flows and the flame arising at thermo-chemical conversion of biomass pellets downstream of a cylindrical channel. Under experimental and numerical investigation was the swirling flow dynamics with the primary axial air supply below a biomass layer and swirling air supply above it. The results indicate that for cold flows the swirling air jet outflow from tangential nozzles leads to the formation of a complex flow dynamics which is influenced both by upstream and downstream air swirl propagation near the channel walls, with correlating swirl-enhanced formation of the upstream and downstream axial flows close to the flow centreline depending on the swirling air supply rate. These axial flows can be completely balanced at their stagnation within the axial recirculation zone. It is shown that at equal boundary conditions for the swirling flame and the cold flows the swirling flow dynamics is influenced by the upstream air swirl-enhanced mixing of the reactants below the air swirl nozzles. This determines the formation of a downstream reaction zone with correlating development of the flow velocity, temperature and composition profiles in the downstream flame regions with improved combustion stability. The low swirl intensity in these regions prevents the formation of a recirculation zone

1. Gupta, A.K., Lilley, D.G., & Syred, N. (1984). Swirl Flows. Abacus Press UK), 588 p.

2. Meier, W., Duan, X.R., & Weigand, P. (2006). Investigations of swirl flames in a gas turbine model combustor: turbulence-chemistry interactions. Combustion and Flame, 144, 225-236.

3. Külsheimer, C., & Büchner, H. (2002). Combustion dynamics of turbulent swirling flames. Combustion and Flame, 131, 70-84.

4. Driscoll, J. F., & Temme, J. (2011). Role of swirl in flame stabilization. In: 49thAIAA Aerospace Sciences Meeting including the New Horizons Forum and Aerospace Exposition, AIAA 2011-108, 1-11.

5. Candel, S., Durox, D., Schuller, T., Palies, P., Bourgouin, J.F., & Moeck, J. P. (2012). Progress and challenges in swirling flame dynamics. Comptes Rendus Mecanique, 340, 758-768.

6. Physics of Swirling Flow (2009). http://www.personal.psu.edu/users/y/x/yxw145/

7. Harvey, J.K. (1962). Some observations of the vortex breakdown phenomenon. J. Fluid Mechanics, 14, 585-592.

8. Fritz, J, Kroner, M., & Sattelmayer, T. (2001). Flashback in a swirl burner with cylindrical premixing zone. Proceedings of ASME TURBO EXPO 2001, 2001GT-0054, p. 10.

9. Stöhr, M., Sadanandan, R., & Meier, W. (2009). Experimental study of unsteady flame structures of an oscillating swirl flame in a gas turbine model combustor. Proceedings of Combustion Institute, 32, 2925-2932.

10. Cheng, R.K., Yegian, D.T., Miyasato, M.M., Samuelsen, G.S., Benson, C.E., Pellizzari, R., & Loftus, P. (2000). Scaling and development of low-swirl burners for low-emission furnaces and boilers, Proceeding of the Combustion Institute, 28, 1305-1313. http://www2.lbl.gov/tt/publications/916pub1.pdf

11. Zaķe, M., Barmina, I., Descnickis, A., Krishko, V., & Gedrovics, M. (2009). Experimental study of the combustion dynamics of renewable & fossil fuel co-fire in swirling flame. Latvian Journal of Physics and Technical Sciences, 46(6), 3-16. http://versita.metapress.com/content/e175095347015913/fulltext.pdf

Latvian Journal of Physics and Technical Sciences

The Journal of Institute of Physical Energetics

Journal Information


CiteScore 2017: 0.46

SCImago Journal Rank (SJR) 2017: 0.226
Source Normalized Impact per Paper (SNIP) 2017: 0.653

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