Microgravity - Science and Technology

, Volume 17, Issue 3, pp 31–38 | Cite as

Experimental study on convergence of droplet streams under microgravity

  • Tsuyoshi Totani
  • Takuya Kodama
  • Kensuke Watanabe
  • Harunori Nagata
  • Isao Kudo


Experiments on the convergence of two droplet streams have been carried out under microgravity in order to develop a technique for converging droplet streams under microgravity and to examine the behavior of droplets in a vacuum and under microgravity after the binary droplets collide with each other. The working fluid is silicone oil with a low vapor pressure. In this study, a method of orienting the droplet generators toward a convergence point has been tested. In all of the 68 experiments conducted under microgravity, it is confirmed that droplet streams are converged. It has been concluded that the method of orienting multiple droplet generators to a convergeing point is effective for converging droplet streams under microgravity. The behaviors of the colliding droplets under microgravity and in a vacuum have been classified into five types. The five types of behavior are mapped on a We (Weber number) — B (impact parameter) diagram. The range of Weber numbers in the experiments is from 200 to more than 3000.


Weber Number Versus Versus Versus Versus Normal Gravity Droplet Generator Droplet Stream 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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© Z-Tec Publishing 2005

Authors and Affiliations

  • Tsuyoshi Totani
    • 1
  • Takuya Kodama
  • Kensuke Watanabe
  • Harunori Nagata
  • Isao Kudo
  1. 1.Graduate School of EngineeringHokkaido UniversitySapporo, HokkaidoJapan

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