Scaling Bubble Entrainment And Dispersion In Vertical Circular Plunging Jet Flows: Freshwater Versus Seawater

نویسندگان

  • Hubert CHANSON
  • Shin-ichi AOKI
چکیده

At a plunging jet, air entrainment may take place downstream of the impingement perimeter. This study investigates air entrainment and bubble dispersion at vertical circular plunging jets in freshwater, salty freshwater and seawater. The results show lesser air entrainment in seawater plunging jets for identical inflow conditions. The average pseudo-chord sizes are between 4 and 6 mm for all water solutions, although more fine bubbles were detected in seawater. It is believed that surfactants and bio-chemicals harden the induction trumpet at plunge point and diminish air entrapment at impingement in seawater.

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تاریخ انتشار 2002