In pipeline flow the pressure gradients for cylindrical capsules differing in density from the carrier liquid are influenced by the interaction between the surface of the capsule and pipe walls. It is shown that pressure gradients for capsules at the point of incipient motion can be calculated directly from the coefficient of friction. For moving capsules, however, the pressure gradients are a function of the capsule velocity, the surface roughness of the capsule and pipe walls and the coefficient of friction. Data are presented to show how capsule pressure gradients change with velocity for various degrees of capsules and pipe surface polish. This change is thought to be due to a gradual transition from solid-solid friction to hydrodynamic lubrication which is accelerated by polishing of the surfaces.

  • Supplemental Notes:
    • Presented at HYDROTRANSPORT 3--Third International Conference on the Hydraulic Transport of Solids in Pipes, Colorado School of Mines, Golden, Colo., May 15-17, 1974. Sponsored by BHRA Fluid Engineering. Complete set of Conference papers available for $45.00.
  • Corporate Authors:

    Colorado School of Mines

    1500 Illinois Street
    Golden, CO  United States  80401
  • Authors:
    • Kruyer, J
  • Publication Date: 1974-5

Media Info

  • Pagination: 10 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00056478
  • Record Type: Publication
  • Source Agency: British Hydrodynamics Research Association
  • Report/Paper Numbers: Paper G5
  • Files: TRIS
  • Created Date: Jul 15 1974 12:00AM