Rod-climbing effect in Newtonian fluids.

نویسندگان

  • Daniel Bonn
  • Mathias Kobylko
  • Steffen Bohn
  • Jacques Meunier
  • Alexander Morozov
  • Wim van Saarloos
چکیده

When a rotating rod is brought into a polymer melt or concentrated polymer solution, the meniscus climbs the rod. This spectacular rod climbing is due to the normal stresses present in the polymer fluid and is thus a purely non-Newtonian effect. A similar rod climbing of an interface between two fluids has therefore been taken as a signature that one of the fluids exhibits normal stress effects. We show here, however, that the effect can occur with simple Newtonian fluids: it occurs when a Taylor-Couette instability happens in the less viscous of the two liquids but not in the more viscous one.

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عنوان ژورنال:
  • Physical review letters

دوره 93 21  شماره 

صفحات  -

تاریخ انتشار 2004