Jet disintegration

A) Flat Liquid Sheets into Quiescent Air Rim-Jet Disintegration. In quiescent air (without an air flow), a liquid sheet issuing from the 2-D nozzle will converge toward the axis of the sheet to form a round j et under the action of surface tension forces. The liquid jet subsequently breaks up into droplets. 

Cb S99 =rf0We 0 333(23.5 + 0.000395 Rez) Best-fit ofprevious experimental data for liquid jet disintegration Miesse[220]... 

Fig. 9.4 Sieve trays with downcomers for liquid systems with (a) high interfacial tension and dual-flow trays for liquid systems and (b) with low interfacial tension. In the case of downcomers, only the phase to be dispersed flows through the holes. The droplets are formed by jet disintegration. In dual-flow trays, both hquids flow through the same holes alternately. The larger drops spUt because of colhsion with the tray.

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 ... 

The effect of a low-pressure atmosphere on jet disintegration was studied by Garner and Henny (21), who reported a marked increase in average drop size with a decrease in... 

Figure 5. Effect of sound waves on jet disintegration (Miesse)...

The burning of liquid strands, which would normally occur in hypergolic streams upstream of the point of jet disintegration, was investigated by McCullough and Jenkins (51), who reported that the burning rate, in inches per second, increased as a power of the ambient pressure. 

Drop formation is probably the most important performance issue, since it affects the overall performance of the printing process. For example, if the jet disintegrates into many small droplets instead of one drop, the placement of the droplets will not be accurate, and the image quality will be very poor. 

If the main factor causing the occurrence of waves is surface tension, then such waves are called capillary waves. In the case of predominance of gravitational forces we can talk about gravitational waves. An illustration of the first case is the outflow of a liquid jet from a nozzle into the air. At some distance from the nozzle, the surface of the liquid jet gets covered by waves, and then the jet disintegrates into drops (the process of jet breakage takes place). The second case is exemplified by ordinary waves on the surface of the water. 

The spectrum of droplets formed when the jet disintegrates is characterized by distribution of drops over diameters /(D) or over volumes /(V), where... 

Distance from the point of jet outflow up to the place of jet disintegration Throttle length... 

This breakup mechanism is similar to that of a jet breakup in still gases. In the presence of a relatively strong crossflow, however, additional instabilities and waves form on the surface of the jet. These instabilities grow larger as the jet deflects and deforms and contribute to the final jet breakup at Xb- We refer to Xb as the column breakup location (CBL). At this location, the jet disintegrates into a number of relatively large droplets, which themselves undergo secondary breakup processes and become smaller as a part of the atomization process. 

With subcooled liquids the jet disintegrates into droplets due to aerodynamic forces after a certain distance of flight. Liquid vaporizes from these droplets. They... 

After leaving the aperture the jet disintegrates due to air resistance and vaporization. Assuming that disintegration is caused by the resistance of air we obtain the erosion velocity Ue... 

These correlations indicate that the existence of void accelerates the jet disintegration significantly. 

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