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

The Korean Society of Mechanical Engineers (대한기계학회)
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Measurement of Size Distributions of Submicron Electrosprays Using a Freezing Method and an Image Processing Technique

냉각법 및 영상 처리기법을 이용한 서브마이크론 정전분무 액적의 크기분포 측정

  • Gu, Bon-Gi (Dept. of Mechanical Engineering, Graduate School of Korea Advanced Institute of Science and Technology) ;
  • Kim, Sang-Su (Dept. of Mechanical Engineering, Korea Advanced Institute of Science and Technology) ;
  • Kim, Yu-Dong (Dept. of Mechanical Engineering, Graduate School of Korea Advanced Institute of Science and Technology) ;
  • Lee, Sang-Yong
  • 구본기 (한국과학기술원 기계공학과) ;
  • 김상수 (한국과학기술원 대학원 기계공학과) ;
  • 김유동 (한국과학기술원 대학원 기계공학과) ;
  • 이상용
  • Published : 2001.10.01
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Abstract

The size distributions of electrospray droplets from the Taylor cone in cone-jet mode are directly measured by using a freezing method and a transmission electron microscope (TEM) image processing technique. These results are compared with the data obtained by an aerodynamic size spectrometer (TSI Aerosizer DSP). The use of glycerol seeded with NaI and a freezing method make it possible to sample droplets with their original sizes preserved. Since pictures of droplets are taken with TEM with very low vapor pressure of the solution, evaporation is suppressed by freezing. For liquid flow rates below 1 nl/sec, the measured droplet diameters by the TEM image processing technique and the aerosizer are in the range of 0.25 to 0.32 m add 0.3B to 0.40m, respectively. Comparing the TEM data with the aerosizer measurements, it has been revealed that the TEM image processing technique can afford more accurate values of droplet size distributions in the submicron range of 0.1 to 0.4m.

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References

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