Effects of Shear Treatment on Drag-reducing Polymer Solutions and Fibre Suspensions

Nature ◽  
1970 ◽  
Vol 226 (5243) ◽  
pp. 352-353 ◽  
Author(s):  
H. D. ELLIS
Keyword(s):  
Polymer Solutions ◽  
Fibre Suspensions ◽  
Drag Reducing Polymer

Laser-Doppler anemometer measurements of turbulent structure in drag-reducing fibre suspensions

1985 ◽  
Vol 152 ◽  
pp. 455-478 ◽  
Author(s):  
W. D. McComb ◽  
K. T. J. Chan
Keyword(s):  
Reynolds Number ◽  
Drag Reduction ◽  
Polymer Solutions ◽  
Reynolds Numbers ◽  
Laser Doppler Anemometer ◽  
Laser Doppler ◽  
Energy Spectra ◽  
Circumferential Velocity ◽  
Fibre Suspensions ◽  
Drag Reducing Polymer

A laser-Doppler anemometer (LDA) was used to measure turbulent velocities in drag-reducing fibre suspensions. Measurements of streamwise velocities (and, in one case, the circumferential velocity as well) were made in flow through a straight pipe at x/d = 190, and at Reynolds numbers in the range 1.4 × 104–5.3 × 104. The fibres used were chrysotile asbestos of high aspect ratio (∼ 106), at a concentration of 300 w.p.p.m. They were dispersed in an aqueous solution of a surfactant (0.5% by weight Aerosol OT). In some experiments, the fibre suspensions were supplemented by a drag-reducing polymer (Separan AP30) at a concentration of 150 w.p.p.m. A complete experiment involved passing a quantity of fibre suspension through the apparatus a number of times (at a given Reynolds number) and measuring the velocity distribution across the pipe during each pass. As the amount of drag reduction generally declined with the number of passes (i.e. due to fibre degradation), this provided a convenient way of varying the percentage drag reduction as an experimental parameter. Results were obtained for mean velocity and intensity profiles, autocorrelations, and one-dimensional energy spectra. The mean period of turbulent bursts was determined by measuring autocorrelations with short sampling times.At the lowest Reynolds number (Re = 1.4 × 104), drag reductions of about 70% were obtained during the first two passes. This was accompanied by a reduction in the streamwise intensity below the level obtained in the surfactant solution alone. (Note: The opposite behaviour is found in drag-reducing polymer solutions, where intensity levels are larger than those in the solvent alone.) A measurement of the r.m.s. circumferential velocity showed an increased level (relative to surfactant alone) during this part of the experiment. During further passes, there was a transition to ‘polymer-like’ behaviour, with increased streamwise intensity, which subsequently declined with pass number (and hence drag reduction) towards the result for surfactant alone. This effect had previously been found in preliminary experiments at Re = 9 × 103 (McComb & Chan 1979). Repetition of the experiment a Re = 1.4 × 104, with the addition of Separan AP30, confirmed the existence of this transition from ‘fibre-like’ to ‘polymer-like’ drag reduction. In this case, the drag reduction was smaller (at about 60%), but the mixed suspension was much more resistant to degradation, with transition occurring at the ninth pass. However, such behaviour was not found at higher Reynolds numbers (Re = 3.2 × 104 and 5.3 × 104), in fibre suspensions where increased streamwise intensities occurred, even at high levels of drag reduction (about 70%).Anomalous streamwise autocorrelations were found during ‘fibre-like’ drag reduction but in the ‘polymer-like’ regime they were very similar to those measured in polymer solution, and showed characteristically increased lengthscales. On the other hand, energy spectra were found to be anomalous in all cases and showed an energy deficit at lengthscales of the same order as the fibre length. Finally, mean bursting periods were found to be much increased, with the increases being about the same as those in polymer solutions at the same Reynolds number and percentage drag reduction.

Diffusion of drag-reducing polymer solutions within a rough-walled turbulent boundary layer

2010 ◽  
Vol 22 (4) ◽  
pp. 045102 ◽  
Author(s):  
Brian R. Elbing ◽  
David R. Dowling ◽  
Marc Perlin ◽  
Steven L. Ceccio
Keyword(s):  
Boundary Layer ◽  
Turbulent Boundary Layer ◽  
Polymer Solutions ◽  
Drag Reducing Polymer

Karman Vortices in the Flow of Drag-reducing Polymer Solutions

Nature ◽  
1970 ◽  
Vol 225 (5231) ◽  
pp. 445-446 ◽  
Author(s):  
V. N. KALASHNIKOV ◽  
A. M. KUDIN
Keyword(s):  
Polymer Solutions ◽  
Drag Reducing Polymer

Gas-liqud slug flow with drag-reducing polymer solutions

AIChE Journal ◽  
1972 ◽  
Vol 18 (4) ◽  
pp. 744-750 ◽  
Author(s):  
R. G. Rosehart ◽  
D. S. Scott ◽  
E. Rhodes
Keyword(s):  
Slug Flow ◽  
Polymer Solutions ◽  
Drag Reducing Polymer

Steady and dynamic shear properties of non-aqueous drag-reducing polymer solutions

1995 ◽  
Vol 34 (6) ◽  
pp. 586-600 ◽  
Author(s):  
Carlos Tiu ◽  
Tony Moussa ◽  
Pierre J. Carreau
Keyword(s):  
Polymer Solutions ◽  
Dynamic Shear ◽  
Shear Properties ◽  
Drag Reducing Polymer

Dynamical behaviour of drag-reducing polymer solutions

1979 ◽  
Vol 5 ◽  
pp. 475-495 ◽  
Author(s):  
O. Scrivener ◽  
C. Berner ◽  
R. Cressely ◽  
R. Hocquart ◽  
R. Sellin ◽  
...  
Keyword(s):  
Polymer Solutions ◽  
Dynamical Behaviour ◽  
Drag Reducing Polymer

Heat transfer to drag-reducing polymer solutions

AIChE Journal ◽  
1969 ◽  
Vol 15 (2) ◽  
pp. 294-297 ◽  
Author(s):  
K. A. Smith ◽  
G. H. Keuroghlian ◽  
P. S. Virk ◽  
E. W. Merrill
Keyword(s):  
Heat Transfer ◽  
Polymer Solutions ◽  
Drag Reducing Polymer

Nucleate boiling in drag‐reducing polymer solutions

1983 ◽  
Vol 27 (1) ◽  
pp. 59-76 ◽  
Author(s):  
D. D Paul ◽  
S. I. Abdel‐Khalik
Keyword(s):  
Polymer Solutions ◽  
Nucleate Boiling ◽  
Drag Reducing Polymer

Laminar, transitional and turbulent annular flow of drag-reducing polymer solutions

2010 ◽  
Vol 165 (19-20) ◽  
pp. 1357-1372 ◽  
Author(s):  
A. Japper-Jaafar ◽  
M.P. Escudier ◽  
R.J. Poole
Keyword(s):  
Annular Flow ◽  
Polymer Solutions ◽  
Drag Reducing Polymer
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