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Droplet dripping

Yatsuzuka, K. Mizuno, Y. Asano, K. Electrification phenomena of pure water droplets dripping and sliding on a polymer surface. J. Electrostat. 1994, 32, 157-171. [Pg.1545]

Remove only the methanol plus a bit of water to ensure that all of the methanol is gone. The droplet size of condensed methanol is much smaller than for water. The methanol has been removed when the small (MeOH) droplets dripping from the condenser coil become much larger (water) droplets. [Pg.215]

Water tight 10-2 10-3 No water droplets dripping from leak (other liquids nmy still escape )... [Pg.174]

Fig. 13.3 Conceptual division of an arbitrary hexahedral element into 40 tetrahedral elements and the resulting surface reconstruction for a droplet dripping test case... Fig. 13.3 Conceptual division of an arbitrary hexahedral element into 40 tetrahedral elements and the resulting surface reconstruction for a droplet dripping test case...
Dripping water (vertically falling droplets) wilt have no harmful effect. [Pg.24]

A small amount of a liquid tends to take a spherical shape For example, mercury drops are nearly spherical and water drips from a faucet in nearly spherical liquid droplets. Surface tension, which measures the resistance of a liquid to an increase in its surface area, is the physical property responsible for this behavior. [Pg.769]

The second approach is to use a specified concenfration of solution. This concentration is normally expressed as a hectolitre concentration and is the grams or milliliters of formulated product per 100 L of water. Here the trees are sprayed until run-off (the point at which the droplets coalesce and start to drip from the leaves). Once this point has been reached, the trees cannot be overdosed, since any additional solution will fall from the trees. This method, therefore, gives the advantages of (a) not overdosing, (b) tree size is irrelevant, and (c) no calculation of tree numbers is required. [Pg.183]

Fogging is formation of small water droplets (visible condensation) on the surface of a polymer film. Undesirable effects may result from fog formation, such as reduction of clarity and dripping. Incorporation of antifogging agents eliminates the reduction of transparency by migration to the surface and increases the polymer surface critical wetting tension. This results in... [Pg.773]

Say you place 50 ml of liquid A (B.P. 50°C) and 50 ml of liquid B (B.P. 100°C) in 250 ml R.B. flask. You drop in a boiling stone, fit the flask in a distillation setup, and turn on the heat. Bubbling starts and soon droplets form on the thermometer bulb. The temperature shoots up from room temperature to about 35°C, and a liquid condenses and drips into the receiver. That s bad. The temperature should be close to 50 °C. This low-boiling material is the forerun of a distillation, and you won t want to keep it. [Pg.157]

Recently, the size and shape of a liquid droplet at the molten tip of an arc electrode have been studied,12151 and an iterative method for the shape of static drops has been proposed. 216 Shapes, stabilities and oscillations of pendant droplets in an electric field have also been addressed in some investigations. 217 218 The pendant drop process has found applications in determining surface tensions of molten substances. 152 However, the liquid dripping process is not an effective means for those practical applications that necessitate high liquid flow rates and fine droplets (typically 1-300 pm). For such fine droplets, gravitational forces become negligible in the droplet formation mechanism. [Pg.126]

From a liquid film such as a water film, the diameter of a drop formed under the action of gravity is calculated to be 9 mm with the above equation. Similarly to the liquid dripping mode, the liquid film breakup mode governed by the dripping mechanism is also typified by large droplets and low liquid flow rates. [Pg.126]

To obtain a large transfer area between raffinate and extract phases, one of the two liquids must be dispersed into drops. Figure 9.2 demonstrates this process schematically at a single nozzle. Similar to a dripping water tap, individual drops periodically leave the nozzle when the volumetric flow rate of the dispersed phase is low. When the flow rate is higher, however, the liquid forms a continuous jet from the nozzle that breaks into droplets. Because of stochastic mechanisms, uniform droplets are not formed. If the polydispersed droplet swarm is characterized by a suitable mean drop... [Pg.373]

The ink for inkjet printers is essentially colored water, and the current formulation of ink is about 75% water, plus dye and glue (Kang 1991, Le 1998, Pond 1999). The ink should flow readily from ihe inkwell to the nozzle, and then to the paper, without dripping or clogging. The viscosity of current inkjet ink is from 2 to 8 cP. The droplets formed should be very uniform in size, and should be as small as possible to increase the resolution. When the droplet hits the paper, the droplet should penetrate the fibers without splatter, which would increase the diameter of the dot on the printed text or picture. The surface tension of current ink is around 45 to 50 dynes/cm, which is much lower than water at 70 dynes/cm. It is believed that if the surface tension is raised from 45 to 65 dynes/cm, the spread (or ratio of diameter of spot on paper/diameter of droplet) would decrease from 3.3 to 1.1. Much higher resolutions... [Pg.278]

As discharge velocity at the nozzle outlet increases, the following states appear in succession dripping, laminar jet breakup, wave disintegration, and atomization. These states of fiow are described in a pi space Re, Fr, Wep, whereby Wep = pv dp/a represents the Weber number formed by the droplet diameter, dp. To eliminate the fiow velocity, v, these numbers are combined to give... [Pg.43]

With higher discharge velocities, laminar jets are produced that disintegrate to droplets at a certain distance from the capillary. The transition from dripping to liquid jet disintegration occurs at higher Weber numbers ... [Pg.44]

Flame retardants are often used in combination with anti-drip agents, which reduce the tendency of the material to form burning droplets in the event of fire (67). Fluorinated polyolefins are preferably used as anti-drip agents (22,67). [Pg.235]

The tower overhead vapor, shown in Fig. 13.6, condenses to a liquid on the outside of the cold condenser tubes. The liquid drips off the tubes. These droplets of liquid are in close contact with the saturated vapor in the condenser shell. This means that the liquid is in equilibrium with the vapor. The condensed liquid is therefore, initially, at its bubble-point temperature. This liquid accumulates in the bottom of the condenser s shell. The submerged tubes then must subcool this liquid. Part of the surface area of the condenser is hence devoted to subcooling liquid, and part is devoted to condensing vapor. [Pg.157]

DNPH. see 2,4-Dinitrophenylhydrazine DOPA, conversion of, 395 Dough, washing, starch isolation, 675-676 DPH. see 1,6-Diphenyl-1,3,5-hexatriene Drip loss in solid foods, 319, 321-322. see also Water retention Droplet concentration in emulsions, 516, 594-596... [Pg.759]

A common way to produce small droplets is to let them drip slowly from a capillary. The the size of the droplet, Dd, depends on surface tension, as, the diameter of the capillary, D, gravity, g, and density of the liquid. Perform a dimensional analysis to determine the dimensionless groups that govern this process. [Pg.203]

Water dripping from a tube will form a droplet supported by surface tension at the tube-water boundary, until the surface tension force can no longer support the droplet. Just before the droplet falls, as shown in Fig. 2, the gravitational force on the droplet is balanced by the surface tension force at the edge of the tube ... [Pg.327]

The simplest method to produce droplets is to drip a liquid slowly out of a capillary under the influence of gravity. Due to the low shear rate, the viscosity of the liquid will, as a rule, have no influence. In this case the target quantity, particle diameter (here droplet diameter) dp, will depend only on the wetted capillary diameter d, the surface tension o and the weight gp of the dripping liquid ... [Pg.12]

Both these fractionation methods permit the contents of the centrifuge tube to drip sequentially into a set of test tubes. Ideally it would be desirable for each test tube or fraction to receive the same volume of solution. Unfortunately this is often not the case. Droplets obtained from the least dense region of the gradient are also the least viscous, and therefore exhibit a smaller amount of surface tension than do droplets obtained from denser regions. Since the size a droplet can attain before falling away from the tube is a function of its surface tension, the drops obtained from the top of the gradient are smaller than those obtained from the bottom. If quantitation of the gradient contents is desired, this problem must be eliminated or appropriate corrections made for it. [Pg.332]


See other pages where Droplet dripping is mentioned: [Pg.2374]    [Pg.2357]    [Pg.132]    [Pg.581]    [Pg.953]    [Pg.441]    [Pg.497]    [Pg.2374]    [Pg.2357]    [Pg.132]    [Pg.581]    [Pg.953]    [Pg.441]    [Pg.497]    [Pg.387]    [Pg.1429]    [Pg.1897]    [Pg.281]    [Pg.209]    [Pg.9]    [Pg.192]    [Pg.316]    [Pg.102]    [Pg.106]    [Pg.123]    [Pg.124]    [Pg.126]    [Pg.127]    [Pg.8]    [Pg.114]    [Pg.765]    [Pg.244]    [Pg.1252]    [Pg.1656]   
See also in sourсe #XX -- [ Pg.233 ]




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