Effect Bernoulli

Bernoulli effect At any point in a conduit through which a liquid is flowing, the sum of pressure energy, potential energy, and kinetic energy is constant. 

The Bernoulli effect—In a rapidly expanding flow, the two phases accelerate differently. For low initial velocities, the ratio of final velocities at the end of expansion, Va/VL, can be approximated by (pL/pG)u2-... 

Figure 4.5 The Bernoulli effect occurs when the flow of fluid over one face of a body is greater than over another, leading to pressure inequalities. Try it (a) hold a pace of paper in both hands, and feel it sag under its own weight, (b) Blow over the paper s upper surface, and see it lift...

The water pump is another example of the Bernoulli effect, and is an everyday piece of equipment in most laboratories, for example being used during Buchner filtration. It comprises a piece of rubber tubing to connect the flask to be evacuated to a pump. Inside the pump, a rapid flow of water past one end of a small aperture inside the head decreases the pressure of the adjacent gas, so the pressure inside the pump soon decreases. 

Spray drying, employed preferentially for inexpensive enzymes on a mass scale, evaporates water by spraying the protein solution through a nozzle at high temperature, utilizing the Bernoulli effect. As contact times are short (on the order of less than 1 s), the enzyme is not deactivated. Not much modeling has been performed on this operation. 

We have seen the effect of changing the diameter of a pipe on the speed of the fluid flowing through the pipe. It turns out that as the speed of a fluid increases, the pressure exerted by the fluid decreases. This phenomenon is called the Bernoulli Effect. The Bernoulli effect provides the lift for airplanes and is why shower curtains get sucked towards you when you first turn on the shower. It also provides the basis for a Venturi flowmeter. 

Finally, it is worth mentioning that the cavitation phenomenon observed in low viscosity liquids is also caused by (explosive) boiling induced by sudden reduction of pressure, such as that occurring in regions behind moving surfaces, such as impellers, or as the result of flow acceleration (Bernoulli effect) (23). 

Bernoulli effect, cavitational bubble formation, 22 Bioceramics... 

High temperature aerosol decomposition, catalyst synthesis, 3 Hydrodynamic cavitation advanced catalysts, ceramics, and electronic materials, 3, 6-bismuth molybdate, 33-34 Bernoulli effect, 22... 

As a result of their form, hollow stirrers utilize the suction generated behind their edges (Bernoulli effect) to suck in gas from the head space above the liquid. As rotating ejectors , they are stirrers and gas pumps in one and are therefore particularly suitable for laboratory use (especially in high pressure autoclaves) because they achieve intensive gas/liquid contacting via internal gas recycling without a separate gas pump [58/1]. A particularly effective type of this stirrer - the pipe stirrer - is depicted in Fig. 28. 

Differential pressure devices consist of two elements—one causes a change in the flow rate of a flowing fluid, which creates a pressure difference (Bernoulli effect) between two sections of the tube or pipe, and the second element measures the resultant Ap. Such a device is nonlinear, since Ois proportional to As a result, the range of Rvalues... 

Figure 20 Patterns of velocity and pressure in a typical LFR 1. Pressure profile in channel I as caused by friction. 2. Pressure profile in channel 11 as caused by friction. 3. Difference between 1 and 2. 4. Pressure profile as caused by Bernoulli effect 5. Total pressure difference across catalyst slab.

The aerosol produced by an air-jet nebulizer (Fig. 3) is generated by a completely different principle. When compressed air is forced through an orifice, an area of low pressure is formed where the air jet exists. A liquid may be withdrawn from a perpendicular nozzle (the Bernoulli effect) to mix with the air jet to form droplets. A baffle (or baffles) within the nebulizer is often used to facilitate the formation of the aerosol cloud. Carrier air (oxygen) can be used to generate the air jet. Alternatively, compressors may be used to generate the airstream. 

Sample Introduction Samples can be introduced into the ICP by argon flowing at about 1 L/min through the central quartz tube. The sample can be an aerosol, a thermally generated vapor, or a fine powder. The most common means of sample introduction is the concentric glass nebulizer shown in Figure 28-9. The sample is transported to the tip by the Bernoulli effect. This transport process is called aspiration. The high-velocity gas breaks up the liquid into fine droplets of various sizes, which are then carried into the plasma. 

Bernoulli effect In atomic spectroscopy, the mechanism by which sample droplets are aspirated into a plasma or flame. j8-amylose That component of starch that serves as a specific indicator for iodine. 

Bernoulli effect venturi used to restrict flow... 

If the feed zone is intended to be a centrifuge, the swirl should not impinge on the catch tray, because the Bernoulli effect at high vapor velocity can reverse flow through a chimney, thus causing maldistribution in the de-entrainment zone. 

Colloidal particles are large enough that any given particle, not in the center of the tube, will experience a pressure difference across its diameter due to the higher velocity on one side than on the other. Thus, the particle will experience a "lift-force" tending to move it away from the wall toward the center of the channel. This "lift-force" is not unlike the aerodynamic lift on an airfoil due to the "Bernoulli effect". 

The Aspirator The most common source of vacuum (approximately 10-20 mm Hg) in the laboratory is the water aspirator, or "water pump," illustrated in Figure 8.7. This device passes water rapidly past a small hole to which a side arm is attached. The water pulls air in through the side arm. This phenomenon, called the Bernoulli effect, causes a reduced pressure along the side of the rapidly moving water stream and creates a partial vacuum in the side arm. 

As is often the case when a new technique is introduced in response to a certain deficiency, a new problem becomes apparent. Wind blowing over plastic films creates a lower air pressure on top of the films than that below causing the films to rise (the Bernoulli effect). This billowing of the films causes additional stresses and may cause damage to the plants. Embossed films are almost immune to this phenomenon since they are more pliable than tubular films and hug the contours more closely when spread out on the ground. 

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