0
Research Papers: Multiphase Flows

Drag Reduction in Turbulent Flow With Polymer Additives

[+] Author and Article Information
Shu-Qing Yang

School of Civil, Mining and Environmental Engineering, University of Wollongong, New South Wales 2522, Australiashuqing@uow.edu.au

J. Fluids Eng 131(5), 051301 (Apr 10, 2009) (8 pages) doi:10.1115/1.3111255 History: Received May 28, 2007; Revised August 02, 2008; Published April 10, 2009

The mean velocity profile and friction factor in turbulent flows with polymer additives are investigated using Prandtl’s mixing-length theorem. This study reveals that the mixing-length theorem is valid to express the drag-reducing phenomenon and that the presence of polymer additives increases the damping factor B in van Driest’s model; subsequently reducing the mixing-length, this interprets that the polymer hampers the transfer of turbulent momentum flux, the velocity is increased, and flow drag is reduced. This study also discusses the onset Reynolds number for drag reduction to occur. The predicted velocity, friction factor, and onset Reynolds number are in good agreement with the measured data in the literature.

FIGURES IN THIS ARTICLE
<>
Copyright © 2009 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Figure 1

The velocity distribution in flows containing polymer additives after Virk (2)

Grahic Jump Location
Figure 2

Relation between the damping factor B and D∗ based on the data shown in Fig. 1

Grahic Jump Location
Figure 3

Comparison of Eq. 12 with the measured velocity profiles

Grahic Jump Location
Figure 4

Velocity distribution inside the near wall region

Grahic Jump Location
Figure 5

Comparison of measured velocity profiles in drag-reducing flows with DNS’s model after Ptasinski (25,35)

Grahic Jump Location
Figure 6

Mean velocity profiles measured by Reischman and Tiederman (38); DR stands for drag reduction

Grahic Jump Location
Figure 7

Linear relation between D∗ and Reynolds number based on Reischman and Tiederman’s (38) data

Grahic Jump Location
Figure 8

Comparison of friction factor between the measured results by Virk (2) and Eq. 24

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In