Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
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Identification of Internal Flow Pattern in Effervescent Atomizers

기체주입노즐의 내부유동양식의 구분

  • 김주연 (한국과학기술원 대학원 기계공학과) ;
  • 이상용 (한국과학기술원 기계공학과)
  • Published : 2000.02.01
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Abstract

An experimental study was conducted to examine the internal flow patterns inside the mixing chamber of effervescent atomizers. The mixing chamber has the rectangular cross section ($8mm{\times}2mm$) and made of transparent acrylic plate for flow visualization. The parameters tested were the air/liquid ratio (ALR), injection. pressure, and the nozzle orifice diameter. Three different flow regimes were observed; bubbly, annular, and intermittent flows. In the bubbly flow regime, the discharged mixture was disintegrated into drops through the bubble expansion and the ligament breakup. On the other hand, in the annular flow regime, the liquid annulus was disintegrated into small drops by the aerodynamic interaction between the phases due to the high relative velocities between the gas and the liquid. In the intermittent flow regime, the bubble-expansion/ligament-disintegration mode and the annulus-disintegration mode appeared alternatively. The correlations representing the transition criteria between the two-phase flow patterns within the mixing chamber were proposed based on the drift-flux models.

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References

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