Swirl flame

Meier, W., Duan, X. R., and Weigand, P, Investigations of swirl flames in a gas turbine model combustor—II. Turbulence-chemistry interactions. Combust. Flame, 144, 225, 2006. 

The controlled flame was found to be largely unaffected by moderate swirl (levels up to 40%) although the stability was slightly reduced. Heavy swirl (beyond 75%) led to a further reduction in stability and intermittent formation of soot. The unforced swirling flame was not nearly as efficient in reducing soot formation as the controlled (forced) flame without swirl. The flame was unstable, quite yellow, and spread out to impinge upon the dump diameter... 

Liquid-fuel pulsations proved to be most effective in a forced flame. Injecting fuel in-phase with air vortices provided the highest temperatures. In both nonswirling and swirling flames, injecting fuel out of phase with air vortices proved to be least efficient. 

The present study is now focusing attention on feedback loop control where forcing will be used to reduce instabilities and minimize pollutants in swirling flames. 

A. Sengissen, A. Giauque, G. Staffelbach, M. Porta, W. Krebs, P. Kaufmann, and T. Poinsot. Large eddy simulation of piloting effects on turbulent swirling flames. Proc. Combust. Inst., 31 1729-1736, 2007. 

Instabilities in Swirling Flames Using Real Time L.D.V., "Proc. Symposium on Turbulent Shear Flows, Penn State University, April 1977. 

Swirling flows are inherently three dimensional. The authors current PIV system measures only two velocity components. A newly acquired stereoscopic PIV system will be used to characterize the 3D flowfield. In addition, pollutant characteristics of high-pressure partially-premixed swirling flames will also be obtained. Together with the PIV velocity and acoustic measurements, a full characterization of both pollutant and noise emissions from such flames will be achieved. It is believed that this will help improve the fundamental understanding of these types of emissions from modern gas-turbine combustors and will provide a valuable database for validating LES models. 

The swirl velocity component, w, is a strong function of radius r at the burner exit, and knowledge of this dependence is essential in order to calculate Swirl numbers. This functionality depends on how swirl is generated. The Swirl number, however, is an important parameter describing the flow of swirling flames and can be used for scale up purposes. 

Multichannel burners In the 1970s when the kilns became shorter with the introduction of dry process with suspension preheater and precal-ciner fired on solid fuels, they were developed in order to reduce the primary air supply and to obtain a short, divergent with strong swirl flame suitable for firing pulverized fossil coal first and petcoke. 

Beltagui, S. A., and Maccallum, N. R. L. "Aerodynamics of Vane Swirled Flames in Furnaces. The Modeling of Vane Swirled Flames in Furnaces." Journal of the Institute of Fuel 49, no. 401 (1976) 183-193. 

Kerr, N. M., and Fraser, D. "Swirl Part 1 Effect on Axisymmetrical Turbulent Jets, Part 2 Effect of Flame Performance and the Modeling of Swirling Flames." Journal of the Institute of Fuel 38 (1965) 519-526. 

Habisreuther P, Philipp M, EickhofF H, Leuckel W Mathematical modeling of mrbrJent swirling flames. In High intensity combustors—steady isobaric combustion, Weinheim, Germany, 2005, Wiley-VCH Verlag, pp 156-175. 

Meier, W., Weigand, R, Duan, X.R., Giezendanner-Thoben, R. Detailed Characterization of the Dynamics of Thermoacoustic Pulsations in a Lean Premixed Swirl Flame. Combust. Flame 150(1-2), 2-26 (2007)... 

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