TURBULENCE PHENOMENA IN DRAG REDUCING SYSTEMS

An analysis based on the Townsend-Bakewell model of the eddies in the wall regions of turbulent shear flows shows that viscoelastic fluid properties must lead to significant reductions in the rate of production of turbulent energy. This analysis in turn leads to the proper form of the similarity laws for drag reducing fluids, heretofore deduced empirically. Design calculations based upon the present results suggest that in large diameter pipelines, or in boundary layers on large objects, drag reduction may not be attainable under conditions of practical interest until fluids having relaxation times an order of magnitude larger than those presently available, but with comparable viscosity levels, are developed or, alternately, until fluids exhibiting Weissenberg numbers which do not change with deformation rate, can be found. ( Author )

  • Supplemental Notes:
    • Revision of report dated 04DEC67
  • Corporate Authors:

    American Institute of Chemical Engineers

    345 East 47th Street
    New York, NY  USA  10017
  • Authors:
    • Seyer, F A
    • Metzner, A B
  • Publication Date: 1969-5

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Filing Info

  • Accession Number: 00007101
  • Record Type: Publication
  • Source Agency: National Technical Information Service
  • Report/Paper Numbers: Tech Rpt
  • Contract Numbers: 2285( 03 )
  • Files: TRIS
  • Created Date: Dec 22 1974 12:00AM