Journal of Fluid Mechanics

Particle-laden tubeless siphon

J. WANG a1 and D. D. JOSEPH a1
a1 Department of Aerospace and Engineering Mechanics, University of Minnesota, MN 55455, USA


A tubeless siphon was created by sucking a 1% aqueous Polyox 1 solution laden with particles from a beaker into a cylinder by moving a piston. The piston speed and particle concentration were varied. At very high rates of withdrawal, all the liquid could be removed before the siphon broke. In this case, the beaker was completely cleaned without a trace of liquid. The addition of small concentrations of small, nearly neutrally buoyant particles greatly enhanced the pulling power of the liquid, reducing the threshold speed of withdrawal at which the beaker was completely cleaned. At speeds of withdrawal smaller than the threshold not all of the fluid–particle mixture is pulled out of the beaker. The amount pulled out first increases, then decreases as the particle concentration is increased.

(Received September 26 2002)
(Revised January 2 2003)


1 Polyox is a registered trademark of Union Carbide.