• Proceedings of the KSME Conference
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• 2001.06d
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• pp.909-914
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• 2001

Fluid properties which are most commonly used to evaluate spray atomization characteristics, are important because they affect velocity and size distribution of droplets. The purpose of this study was to incorporate the significant characteristics in atomization process of industrial etching spray and how each of them affects the design of precise pressure-swirl nozzles. The experiment was carried out with different viscosity and density of fluid. The macro characteristics of liquid spray, such as the spray angle and shape were captured by PMAS and the micro characteristics of liquid spray, such as droplet size and velocity were obtained by PDA. The mean velocity and SMD of droplets were measured along axial and radial direction. It was found that the higher viscosity and density resulted in the larger SMD and the lower mean velocity of droplets.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.12
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• pp.1813-1820
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• 2001

The purpose of this study was to investigate the significant characteristics in atomization process of industrial etching spray fur the design or Precise pressure-swirl nozzles. The experiment was carried out with different viscosities and densities of the liquid. The macro characteristics of liquid spray, such as the spray angle and breakup process were captured by PMAS and the micro characteristics of liquid spray. such as droplet size and velocity measurements were obtained by PDA. The droplet axial and radial velocity and SMD were measured along axial and radial direction. The RMS of two velocities was measured along radial direction. It was found that the fluid with higher kinematic viscosity resulted in the larger SMD and the lower mean droplet velocity. And we could divide breakup processes into three regions that is atomization, non-dilution and dilution one in spray of pressure-swirl nozzle. The radial as well as axial velocity of droplet played an important role in the atomization process of higher kinematic viscosity fluid.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.24 no.10
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• pp.1300-1308
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• 2000

The objectives of this study was to investigate the spray characteristics of single spray and twin spray in the overlap region such as mean axial velocity, mean radial velocity, mean droplet size and probability density function of droplet size. A phase doppler anemometer was used as the measurement system for droplet size and velocity. In case of single spray, injection pressure was varied from 0.2MPa to 0.7MPa. Mean axial velocity, mean radial velocity and droplet size were decreased as the distance below nozzle tip was increased. In case of twin spray, the spray characteristics were measured by varying the distance between two nozzles from 127mm to 155mm. In the overlap region, the boundary of the overlap region was determined by obtaining the distribution of mean axial and radial velocity. Droplet size was increased as the distance from nozzle tip was increased. It was found that the distribution of droplet size for twin spray in the overlap region was different to single spray.