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Spontaneous Steady Capillary Flow in Partially Coated Tubes
AIChE Journal (1997)
  • Mark M. Weislogel, Portland State University

A spontaneous, steady capillary flow is produced for a liquid index in a circular tube that is partially coated with a surface modifier to create a discontinuous wetting condition between upstream and downstream portions of the tube. As a means of demonstrating that the flow configuration may prove useful as a diagnostic tool in studies concerning capillarity and the physics associated with the moving contact line, average steady velocities are predicted and compared against a large experimental data set that includes the effects of tube dimensions and fluid properties. To access a wider range of tube diameters (0.516-9.88 mm), experiments are performed employing ''U-tubes'' tested in the low-gravity environment of a drop tower, in addition to straight capillary tubes tested horizontally in a laboratory. The sensitivity of the steady capillary flow to surface cleanliness is dramatic.

Publication Date
March, 1997
Citation Information
Mark M. Weislogel. "Spontaneous Steady Capillary Flow in Partially Coated Tubes" AIChE Journal Vol. 43 Iss. 3 (1997)
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