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On Some Local Aspects of Turbulent Drag Reducing Flows of Dilute Polymers and Surfactants

  • A. Gyr
  • A. Tsinober
Part of the Fluid Mechanics and its Applications book series (FMIA, volume 36)

Abstract

Local aspects of turbulent drag reducing flows were studied via evaluating the surrogate dissipation, the third order velocity structure function, the third order moment of the derivative of the velocity fluctuations of a flow in water and in drag reducing solutions (polymer and surfactants) at the same flow conditions. While both the dissipation and the enstrophy production are reduced strongly for both drag reducing flows, they exibit some qualitative differences. Namley, in a polymer solution flow the disispation is increasing with the distance from the wall, whereas it is decrasing for the flow of surfactant solution. The inhibition of enstrophy production is stronger in the near wall region in the polymer solution, while for the surfactant the tendency is opposite. Thus there are clear indications on the qualitative differences in mechanisms in the two drag reducing flows.

Keywords

Structure Function Drag Reduce Inertial Subrange Dilute Polymer Solution Local Aspect 
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References

  1. G.K. Batchelor & A. A. Townsend (1949) The nature of turbulent motion at large wave-numbers. Proc. Roy. Soc. A 199, 238–255ADSGoogle Scholar
  2. A. Gyr & H.-W. Bewersdorff (1995) Drag reduction of turbulent flows by additives. Kluwer Academic Publishers, Dordrecht, Boston, LondonGoogle Scholar
  3. A.N. Kolmogorov (1941) Dissipation of energy in locally isotropic turbulence. Dokl. Akad. Nauk SSSR 32, 16–18zbMATHGoogle Scholar
  4. Stiier & A. Gyr (1996) Fractal dimension and intermittency coefficients for various flow variables in Newtonian and non-Newtonian turbulent flows. J. Non Newtonian Fluid Mech.62, 207–224CrossRefGoogle Scholar
  5. G.I. Taylor (1938) Production and dissipation of vorticity in a turbulent fluid. Proc. Roy. Soc. Lond. A 164, 15–23ADSzbMATHCrossRefGoogle Scholar

Copyright information

© Kluwer Academic Publishers 1996

Authors and Affiliations

  • A. Gyr
    • 1
  • A. Tsinober
    • 2
  1. 1.Inst. of Hydromechanics and Water Resources ManagementSwiss Federal Institute of TechnologyZurichSwitzerland
  2. 2.Department of Fluid Mechanics and Heat Transfer, Faculty of EngineeringTel-Aviv UniversityTel-AvivIsrael

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