Measurement of Liquid Viscosities in Tapered or Parabolic Capillaries.
The possibility of using tapered or parabolic capillaries for measurement of liquid viscosities is investigated both experimentally and theoretically. It is demonstrated that even small deviations in capillary radius from a constant value may substantially affect measurement results. Equations are derived which allow correct analysis of the measurement results in tapered or parabolic capillaries. The following cases are analyzed: a water imbibition into a tapered or parabolic capillary and displacement of one liquid by another immiscible liquid in tapered or parabolic capillaries. Two possibilities are considered: (a) the narrow end of the capillary as capillary inlet and (b) the wide end of the capillary as capillary inlet. Copyright 1999 Academic Press.
Institute of Physical Chemistry, Russian Academy of Sciences, 31 Leninsky pr., Moscow, 117915, Russia
AP
Ershov
ZM
Zorin
VM
Starov