Burners photograph

Figure 4.1.2 is a photograph of a coimterflow burner assembly. The experimental particle paths in this cold, nonreacting, counterflow stagnation flow can be visualized by the illumination of a laser sheet. The flow is seeded by submicron droplets of a silicone fluid (poly-dimethylsiloxane) with a viscosity of 50 centistokes and density of 970 kg/m, produced by a nebulizer. The well-defined stagnation-point flow is quite evident. A direct photograph of the coimterflow, premixed, twin flames established in this burner system is shown in Figure 4.1.3. It can be observed that despite the edge effects.

Photograph of a counterflow burner system and the nonreacting flow visualization using a laser sheet. 

Photographs of a simple coaxial burner and the resulting sample flame images, viewed diagonally from the bottom, (a) A preliminary setup. Coaxial ethylene/air flames are formed under the following conditions (b) U, = 1I and = 0.8—flat flame (c) Uj = and... 

Instantaneous schlieren photographs of turbulent Bunsen burner flames at P = 0.1 MPa (left) and P = l.OMPa (right). The flow at U = 2.0m/s is made turbulent, thanks to a perforated plate with hole diameter d = 2.0mm. The burner exit diameter is 20mm. (Reprinted from Frank, J.H., Kalt, P.A., and Bilger, R.W., Combust. Flame, 116, 220, 1999. With permission. Figure 9, p. 238, copyright Elsevier editions.)... 

The effects of excessive temperatures on reformer tubes are in fact quite dramatic. Fig. 24 shows photographs of reformer tube banks with poor performance and tube over-heating. In Fig. 24a, the flame from the burner is visible in the top of the photograph. On several of the tubes clear evidence of hot bands... 

Figure 10.27 A photograph of a screw in a PTA welding lathe a) natural gas burners are heating the screw billet to a temperature of about 400 to 430 °C, and b) the plasma arc of the PTA welder is visible in this photograph (courtesy of Jeffrey A. Kuhman of Glycon Corporation)...

It is well known that in a jet flame blow-out occurs if the air-fuel mixture flow rate is increased beyond a certain limit. Figure 18.3 shows the relationship between the blow-out velocity and the equivalence ratio for a premixed flame. The variation of blow-out velocity is observed for three different cases. First, the suction collar surrounding the burner is removed and the burner baseline performance obtained. Next, the effect of a suction collar itself without suction flow is documented. These experiments show that for the nozzle geometry studied, the free jet flame (without the presence of the collar) blows out at relatively low exit velocities, e.g., 2.15 m/s at T = 1.46, whereas for > 2 flame lift-off occurs. When the collar is present without the counterflow, the flame is anchored to the collar rim and blows out with the velocity of 8.5 m/s at T = 4. Figure 18.4a shows the photograph of the premixed flame anchored to the collar rim. The collar appears to have an effect similar to a bluff-body flame stabilizer. The third... 

Figure 9. Comparison of direct photographs of a laminar and turbulent flame at the same flow rate, fuel-air ratio, and burner size...

Another thermocouple and pyrometer indicate the flame temperature at the coating surface. The burner setup is designed to apply the desired temperature for the given period of time. For example, a temperature of 1750 F. can be reached in 1 minute and then held constant tor 0.5 hour. Figure 3 is a photograph of a typical fire-retardant test setup. 

Fig. 3.0. View of spinning cup sulfur burner from inside sulfur burning furnace - burning capacity 870 tonnes of molten sulfur per day. The thermocouple at top and central blue sulfur-rich flame are notable. Photograph courtesy of Outokumpu OYJ. www.outokumpu.com...

FIGURE 5.2. Photograph of a natural gas-air flame on a rectangular burner, with very small magnesium oxide particles introduced into the flow and illuminated stroboscopically in order to make the gas streamlines visible (from [11], courtesy of B. Lewis and of Academic Press). 

Figure 10 Photographs of the flame tunnel, with the control panel at the right hand side, and the flame tunnel in the middle. The burner is located at the top (not shown). At the flont side, the three injection nozzles for CEB material are visible. Through the opening in the mid e, the clear flame from diesel ts visible (right).

Photograph of a natural draft burner. (From Baukal, C. E., Heat Transfer in Industrial Combustion, Boca Raton, FL CRC Press, 2000 courtesy of CRC Press.)... 

See color insert following page 424.) Left Visualization of burners in ceU D based on virtual test results. Right Photograph of burner in cell D. (From Boisvert, P. G., Majeski, A., Runstedtler, A., and Chui,... 

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