Journal of ILASS-Korea (한국분무공학회지)

Institute for Liquid Atomization and Spray Systems-Korea (한국분무공학회)
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Atomization Characteristics of Effervescent Twin-fluid Nozzle with Different Nozzle Shapes

노즐 형상에 따른 Effervescent 이유체 노즐의 분무특성

  • 이상지 (경북대학교 기계공학과) ;
  • 홍정구 (경북대학교 기계공학과)
  • Received : 2017.08.09
  • Accepted : 2017.09.22
  • Published : 2017.09.30
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Abstract

An experimental study was carried out to investigate the spray characteristics of non-circular effervescent twin-fluid nozzles. For this purpose, two types of non-circular nozzles (E1, E2) and circular nozzle (C) were used. Three types of aerorators with hole diameters of 1.2, 1.7 and 2.1 mm were used. Each aerorator has a total of 12 holes. It is defined by area ratio which is ratio of exit orifice area and aerator hole area. Experiments were carried out by controlling the amount of air flowing after fixing the flow rate of the liquid, and the nozzle internal pressure and SMD were measured, and the jet image was taken from the nozzles. The discharge coefficients of the three kinds of nozzles were compared with the used in plain orifice's equation and the Jedelsky's equation, and the Jedelsky's equation was found to be about 3 times larger. In addition, empirical formula based on ALR, which is the largest variable in Jedelsky's equation, was derived. The droplet sizes(SMD) were found to be smaller in the non-circular shape than in the circular shape, which is concluded to be caused by the difference of the discharge coefficients.

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References

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