Tulip shape

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. 

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.)... 

Other snare devices that potentially can be used for embolectomy include (1) the Alligator Retrieval Device, which is a retriever with grasping jaws attached to the tip of a flexible wire designed to be used in conjunction with 0.21-inch micro-catheter " and (2) the EnSnare device, which has a tulip-shaped, three-loop design that opens distally. These devices, which are approved for foreign body removal/coil retrieval, have not been reported in embolectomy for stroke treatment. 

Sylvania cool white fluorescent room lights. For aroma and flavor evaluations, samples from winery "B" were presented first as a set, followed by samples from winery "A". Each set consisted of a sample from each of the four radiation levels presented in random order. For color evaluation the eight samples were presented simultaneously. For each evaluation, 20 ml of wine were presented in a tulip-shaped glass covered with a watch glass. 

Fig. 103. Cryosublimation apparatus, a. Stopcock arrangement for evacuation. The small donor and receptor tubes are used in the cryosublimation of the 15-m1-samples, b. Larger tulip-shaped vessels used for lyophilization of 150-/d. samples through the same stopcock arrangement as in a. c. Cap used for sealing receptor tubes. The platinum net, shown in the distilling tube in a, traps any solid flakes of protein which may fly over during cryosublimation (Linderstr0m-Lang, 1955a).

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

The dramatic dynamics of the flame-shape change shown in Figure 5.3.1, along with its proposed relationship to the flame instability and flame-generated flow, has periodically sparked an interest in its study. Before reviewing this flame-shape transition phenomenon, it will be useful to trace the history of the "tulip" name and distinguish this particular flame shape from the myriad of others with which it is often equated or confused. 

In 1957, a flame propagating in a long tube under conditions resulting in a deflagration to detonation transition (DDT) was given the name "tulip" by Salamandra et al. [7]. This term was subsequently commonly applied in detonation studies to describe this typical shape [8,9]. Figure 5.3.2 shows a few... 

Rotating camera images of a CO/O2 flame undergoing the inversion from the hemispherical cap flame to an inverted shape that is now considered a tulip or perhaps more accurately a "two-lip" flame. The flame propagates in a 20.3 cm long closed cylindrical tube of 2.5 cm diameter. (Adapted from EUis, O.C. de C. and Wheeler, R.V., /. Chem. Soc., 2,3215,1928.)... 

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. 

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. 

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. 

The classic pathway is triggered by the formation of factor Cl at IgG or IgM on the surface of microorganisms (left). Cl is an 18-part molecular complex with three different components (Clq, Clr, and Cls). Clq is shaped like a bunch of tulips, the flowers of which bind to the Fc region of antibodies (left). This activates Clr, a serine proteinase that initiates the cascade of the classic pathway. First, C4 is proteolytically activated into C4b, which in turn cleaves C2 into C2a and C2b. C4B and C2a together form C3 convertase [1], which finally catalyzes the cleavage of C3 into C3a and C3b. Small amounts of C3b also arise from non-enzymatic hydrolysis of C3. 

Perhaps the best-loved of the springflowering bulbs, tulips have been admired and prized for centuries. Plant breeders have developed thousands of hybrids and cultivars from the more than 100 species in this genus. Divided into 15 divisions, based on bloom time, flower form, and parentage, tulips bear cup-shaped blossoms on 6"-24" tall flower stalks. Flowers come in all colors except true blue bicolors are common. Thick, 6"-8" long, straplike leaves surround flower stems. 

Cl (multi-subunit) Clq 83-125 460,000 Requires Ca " " for subunit association Shaped like a tulip with a stalk that contains... 

In industry practice, other than circular burners, flare tips such as slot burner, Coanda or tulip tips (Kaldair flare systems of John Zink Company), and multiple jet burners are also employed to meet specific flaring needs. Further investigations on elliptic and other noncircular shapes at different values of R need to be conducted in order to understand the applicability of such burners for flare tips. 

The Israeli government is now planning for four artificial islands to be completed in 2013, off the coasts of Tel Aviv, Herzliya, Netanya and Haifa. Each island will house some 20,000 people and offer the employment opportunity of some 10,000 jobs at least. The islands should help with overcrowding in the coastal Israeli cities and might even be employed to do the same in Gaza. A well thought out macroengineering project proposal has also been presented in The Netherlands to create artificial islands, perhaps in the shape of a tulip, in the North Sea. 

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