Tulip flame closed tubes

Tulip Flames The Shape of Deflagrations in Closed Tubes.93... 

Tulip Flames in Relahvely Short Closed Tubes.96... 

Comparison between tulips, (a) Image of an actual tulip flower that has been rotated and sized for comparison (b) the tulip shape noted by Salamandra et al. [7] in flames on their transition to detonation and (c) the inverted flame shape identified by Ellis and Wheeler [5] in closed tubes that is now being called a tulip flame. The image to the right is simply a negative of that to its left. 

However, despite this misnomer, when interest in the closed-tube flame of the Ellis-type resurfaced in the mid-1980s, the researchers involved were also aware of the DDT tulips and the name transferred to the cusped laminar flame transition [11-14]. An example of a flame image from this era is shown in Figure 5.3.4, and the "tulip" name is now used routinely to... 

Flame shape images and traces extracted from the high-speed schlieren movie (5000 frames/s) of a stoichiometric methane/air flame going through a tulip inversion while propagating in a square cross-section (38.1 mm on the side) closed tube. 

Tulip Flames in Relatively Short Closed Tubes... 

A classic self-light stroboscopic image of a premixed flame undergoing a tulip inversion in a closed tube. There is an interval of 4.1 ms between the images of a water vapor saturated CO/Oj flame arranged to have a flame speed comparable with that of a stoichiometric methane/air flame. The tube is 2.5 cm in diameter and 20.3 cm long. (Adapted from Ellis, O.C. de C. and Wheeler, R.V., /. Chem. Soc., 2,3215,1928.)... 

Dunn-Rankin, D. and Sawyer, R.R, Tulip flames Changes in shape of premixed flames propagating in closed tubes. Experiments in Fluids, 24,130-140,1998. 

In Chapter 5.3, D. Dunn-Rankin discusses the shape of deflagrations in closed tubes and the conditions under which it assumes the form of a tulip. The propagation of a premixed flame in closed vessels has been studied from the nineteenth century. The tulip flame is an interesting example of flame-flow interaction originating from the Landau-Darrieus instability. 

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