Tulip flame formation

Tulip-flame formation begins simultaneously with the rapid decrease in the flame area that accompanies the flame quench at the sidewalls of fhe combustion vessel... 

Dunn-Rankin, D., Barr, P.K., and Sawyer, R.E., Numerical and experimental study of "Tulip" flame formation in a closed vessel, Twenty-First Symposium (International) on Combustion, The Combustion Institute, Pittsburgh, pp. 1291-1301, 1986. 

Formation of a tulip flame is relatively insensitive to mass loss and endwall geometry... 

Velocity vectors of the gas flow measured using laser Doppler anemometry inside a closed chamber during the formation of a tulip flame. Images of the flame are also shown, though the velocity measurements required many repeated runs, hence, the image is only representative. The chamber has square cross sections of 38.1mm on the side. The traces in the velocity fields are the flame locations based on velocity data dropout. The vorticity generated as the flame changes shape appears clearly in the velocity vectors. 

Laser Doppler anemometry data showing the axial velocity along the centerline of a 380 mm long closed chamber during the formation of acetylene/air tulip flames of different equivalence ratios. The velocity is measured 265 mm from the ignition thus, the tulip shape is already formed before the flame reaches the measurement point. This work shows the behavior similar to the results described in Figure 5.3.9. (Adapted from Starke, R. and Roth, R, Combust. Flame, 66,249,1986.)... 

Jeung, I., Cho, K., and Jeong, K., Role of flame generated flow in the formation of tulip flame, paper AlAA 89-0492, 27th AlAA Aerospace Sciences Meeting, Reno, Nevada, January 9-12,1989. 

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