Flat spray atomizer

Figure 2.5. Schematic of a flat spray atomizer used for paint spray.

In the empirical correlation proposed by Kato et al.,[503] the mean droplet size is inversely proportional to the water pressure, with a power index of 0.5 for conical shaped annular-jet atomizers, and 0.7-1.0 for V-shaped flat-jet atomizers. This suggests a lower efficiency of the annular-jet atomizers in terms of spray fineness at high water pressures. The data of Kato et al.15031 were obtained for water pressures lower than 10 MPa. Seki et al.15021 observed the similar trend in the water atomization of nickel and various steels at higher water pressures (>10 MPa). Since k is dependent on both... 

External-mixing air-assist atomizers. Derived from ethanol (glycerin)-air spray data with initial thickness of flat circular sheet up to 0.7 mm and varied air impingement angles Sampled with oil-coated slides... 

The suspended flame rotary burner produces atomization of the oil by throwing it off as a spray from a cone, cup, or disk, rapidly revolving about a vertical axis. The spray is supported by the air stream and burns in a flat, circular flame. 

The great flexibility of the air spray gun is its chief advantage. The nature of the atomization produced with a given material is easily controlled by the operator. He can also control the distribution of this spray in the pattern being produced by the gun. He simply adjusts a valve on the gun that modifies the ratio of material to air and the atomization can be made finer or coarser at his will. The control of another valve allows him to readily change the pattern shape from round to a flat fan. 

Knoll, K. E., and Sojka, P. E., Flat-Sheet Twin-Fluid Atomization of High-Viscosity Fluids, Part I Newtonian Fluids, Atomization Sprays, Vol. 2, 1992, pp. 17-36. 

Dry spray dry, flat pebbly surface Spray gun too far from surface, atomization too high, wrong soivent Change application method reduce atomization, change solvent. 

In Fig. 16.20, this liquid film is shown at the outer nozzle geometry of a flat nozzle. It develops since the bubbles burst does not only yield a velocity component in spray flow direction, but additionally a velocity component of fluid toward the nozzle. If there is a plain nearby, as is the case for a flat nozzle outlet geometry, the Uquid can accumulate and is then sheared off by liquid exiting the nozzle. Ligaments and coarse droplets are formed. If a pointed nozzle is used, the probability for the Uquid to be deposited at the atomizer body is smaller. Hence, there are less coarse droplets in the spray. 

Applications requiring speed and/or precision over large flat areas utilize roll contact. One-part liquid adhesives can be applied by atomization using air or airless spraying. Two-part adhesives must be metered or mixed first. 

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