Bubbles photographs

Alternatively, the camera is kept at a fixed distance, and a scale is first photographed. The ratio of the image size to the actual size gives the reduction ratio. If the camera is then positioned at the same distance and the bubble photographed, the actual dimension of the bubble can be obtained from the image size by dividing it by the reduction ratio. 

Fig. 5.12 Collapsing bubble in a liquid on a horn surface bubble photograph (a), sequence of events on cavitation (b)...

Carbon dioxide beer bubbles—(Photographer Ildar Sagdejev)— http //commons.wikimedia.Org/wiki/File 2009-03-21 Beer brewing bubbles.jpg... 

Fig. 1. Photograph illustrating the microstmcture of the foam which stiU persists two hours after shaking an aqueous solution containing 5% sodium dodecylsulfate. The bubble shapes ate more polyhedral near the top, where the foam is dry, and more spherical near the bottom, where the foam is wet.

The prediction of drop sizes in liquid-liquid systems is difficult. Most of the studies have used very pure fluids as two of the immiscible liquids, and in industrial practice there almost always are other chemicals that are surface-active to some degree and make the pre-dic tion of absolute drop sizes veiy difficult. In addition, techniques to measure drop sizes in experimental studies have all types of experimental and interpretation variations and difficulties so that many of the equations and correlations in the literature give contradictoiy results under similar conditions. Experimental difficulties include dispersion and coalescence effects, difficulty of measuring ac tual drop size, the effect of visual or photographic studies on where in the tank you can make these obseiwations, and the difficulty of using probes that measure bubble size or bubble area by hght or other sample transmission techniques which are veiy sensitive to the concentration of the dispersed phase and often are used in veiy dilute solutions. 

Luft-bestandigkeit, /. stability in air, resistance to air. -bestandteil, m. constituent of air. -bild, n. aerial photograph (Optica) aerial image, -blaschen, n. (small) air bubble, -blase,/, air bubble air pocket air bladder, -bleiche, /. open-air bleaching, -bombe, /. aerial bomb, -brennstoffgemisch, n. fuel-air mixture. 

Gal-Or and Resnick (Gl) have developed a simplified theoretical model for the calculation of mass-transfer rates for a sparingly soluble gas in an agtitated gas-liquid contactor. The model is based on the average gas residencetime, and its use requires, among other things, knowledge of bubble diameter. In a related study (G2) a photographic technique for the determination of bubble flow patterns and of the relative velocity between bubbles and liquid is described. 

The flow patterns of agitated liquid have been studied extensively (Al, B11, F6, K5, M6, N2, R12, V5), usually by photographic methods. Apparently no work has been reported on bubble-flow patterns and relative velocities in agitated gas-liquid dispersions. Some simple pictures have been presented that only show the same details that may be seen with the unaided eye (Bll, F6, Y4). 

A fiber-diffraction pattern is recorded on a flat-film camera in which the fiber-to-photographic film distance is typically in the range of 3 to 4 cm. During exposure to X-rays, the specimen chamber is continuously flushed with a slow and steady stream of helium gas that has been bubbled through a saturated salt solution so that (a) the fiber is maintained at a constant desired r.h. and (b) fogging of the photographic film from air scattering is reduced. 

Fig. 5.1a-j Representative photographs of flow patterns in the 1.097 mm diameter circular test section. Test section (a), (b) bubbly (c), (d) slug (e), (f) churn (g), (h) slug-annular (i), (j) annular. Reprinted from Triplett et al. (1999a) with permission... 

C21-0095. A company that manufactures photographic film generates 2550 L/day of aqueous waste containing 0.125 g/L of Br ions. To recover the bromine in the form of Bf2, the company bubbles CI2 gas through this waste. Calculate the volume of gas that is consumed daily if the gas is delivered at 1.05 atm and 21 °C. 

Figure 3.18 A typical photograph defining the bubble boundary layer (pi - 500 psia, Vi - 1 ft/sec. 7 a, - 7] = 200°F, q/A = 0.804 x 10f) Btu/hr ft2). (From Jiji and Clark, 1964. Copyright 1964 by American Society of Mechanical Engineers, New York. Reprinted with permission.)...

The bubble behavior near the boiling crisis is three-dimensional. It is hard to show a three-dimensional view in side-view photography, because the camera is focused only on a lamination of the bubbly flow. Any bubbles behind this lamination will be fussy or even invisible on the photograph, but they can be seen by the naked eye and recorded in sketches as shown in Section 5.2.3. For further visual studies, the details inside bubble layers (such as the bubble layer in the vicinity of the CHF) would be required. Therefore, close-up photography normal and parallel to the heated surf ace is highly recommended. 

Cumo et al. (1969) reported that the pressure effect on the bubble diameter is linear in a Freon-114 flow, as shown in Figure 5.43. They tested the two-phase Freon-114 flow in a vertical rectangular test section at a mass flux of 100 g/cm2 s (0.737 x 106 lb/ft2 hr). The average bubble diameters at various system pressures were obtained from high-speed photographic recordings. The effect of reduced pressure, p pci, on the average diameter of Freon bubbles is correlated as... 

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