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(analytical chemistry)
In flame spectrometry, conversion of a volatilized sample into free atoms.
A process in which the chemical bonds in a molecule are broken to yield separated (free) atoms.
(mechanical engineering)
The mechanical subdivision of a bulk liquid or meltable solid, such as certain metals, to produce drops, which vary in diameter depending on the process from under 10 to over 1000 micrometers.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.


The process whereby a bulk liquid is transformed into a multiplicity of small drops. This transformation, often called primary atomization, proceeds through the formation of disturbances on the surface of the bulk liquid, followed by their amplification due to energy and momentum transfer from the surrounding gas.

Spray formation processes are critical to the performance of a number of technologies and applications. These include combustion systems (gas turbine engines, internal combustion engines, incinerators, furnaces, rocket motors), agriculture (pesticide and fertilizer treatments), paints and coatings (furniture, automobiles), consumer products (cleaners, personal care products), fire suppression systems, spray cooling (materials processing, computer chip cooling), medicinal (pharmaceutical), and spray drying (foods, drugs, materials processing). Current concerns include how to make smaller drops (especially for internal combustion engines), how to make larger drops (agricultural sprays), how to reduce the number of largest and smallest drops (paints and coatings, consumer products, medicinals, spray drying), how to distribute the liquid mass more uniformly throughout the spray, and how to increase the fraction of liquid that impacts a target (paints and coatings, spray cooling, fire suppression).

Spray devices (that is, atomizers) are often characterized by how disturbances form. The most general distinction is between systems where one or two fluids flow through the atomizer. The most common types of single‐fluid atomizers are pressure (also called plain‐orifice, hydraulic, or pneumatic), pressure‐swirl, rotary, ultrasonic (sometimes termed whistle or acoustic), and electrostatic. Twin‐fluid atomizers include internal‐mix and external‐mix versions, where these terms describe the location where atomizing fluid (almost always a gas) first contacts fluid to be sprayed (almost always a liquid).

While primary atomization is important, because of its role in determining mean drop size and the spectrum of drop sizes, subsequent processes also play key roles in spray behavior. They include further drop breakup (termed secondary atomization), drop transport to and impact on a target, drop evaporation (and perhaps combustion), plus drop collisions and coalescence. In addition, the spray interacts with its surroundings, being modified by the adjacent gas flow and modifying it in turn. See Particulates

McGraw-Hill Concise Encyclopedia of Engineering. © 2002 by The McGraw-Hill Companies, Inc.


The formation of tiny droplets or a very fine spray, as produced by impinging jets of air on a small stream of paint in spray painting.
McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.
References in periodicals archive ?
It was determined through visual analysis of air spray (55 psi, fan nozzle) patterns that the dynamic uniaxial extensional viscosity is the dominant parameter in controlling the atomization and sprayability of these simple W-SP blends.
Therefore, in comparison with highly pressurized atomization, uniform spray patterns came out with a steadily increasing spray width as shown in Figure 3(b) and constant spherical droplet size distribution owing to the small droplet diameters.
Therefore, since oil atomization takes place in the cylinder and the atomized oil leaves the compressor through the high-pressure discharge system, it is safe to state that the atomized oil does not interfere with the temperature measurements.
Details of CaBER technique and its useful applications can be found elsewhere (13), In carrying out the measurements and analysis of CaBER, it should be reminded that the strain rate of the extensional deformation may not be equivalent to the strain rate imposed during atomization process.
Causes can be too much air for atomization, the fan pattern is too wide, or the coating's surface tension is too high.
The objective was to determine the flow characteristics of the gas inside the nozzle and flow area and compute the temperature of gas and molten metal for atomization at the nozzle exit and their pre-heating requirement to prevent the chilling effect along with the heat transfer analysis.
By combining the latest atomization and irrigation technologies, as many as 4 medications may be combined and administered in less than 2 minutes.
The kinetic energy of the fuel as it passes through the nozzle is used to achieve atomization. Increasing the pressure of the fluid increases the available energy, reducing droplet size.
Knowledge of this coefficient and its changes caused by the atomizer dimensions, liquid properties and atomization condition is the basic condition that allows the design of pressure swirl atomizer.
New "maximum delivery" air nozzles are said to provide better atomization with Jess material and air consumption.
The new Maximum Delivery air nozzles provide better atomization with less material and lower air consumption, white spraying a wide range of material, the company adds.