Influence of polymer conformation on turbulent drag reduction

Journal Article · Mon Sep 01 04:00:00 EDT 1975 · AIChE J.; (United States)

DOI:https://doi.org/10.1002/aic.690210532· OSTI ID:6574589

White, D Jr; Gordon, R J

In recent years, the search for more efficient turbulent drag reducers has motivated a number of interesting studies on molecular conformation and flexibility. The experimental results in this study support the concept that increased polymer extension in solution leads to better drag reduction. However, the elevated solution viscosities of highly extended conformations may offset any drag reduction enhancement at low Reynolds numbers and must be carefully accounted for. The friction factors for polyacrylamide or polyacrylic acid in deionized water, in high pH solution, and in 0.1M sodium chloride solution tend to merge together at high values of N/sub Re/, suggesting that in each solution the polymer coils approach the same degree of extension. The much higher value of the friction factor in low pH solution implies that the polymer coils have become stiffened, suggesting the presence of strong intermolecular bonding, most probably in the form of hydrogen bonds. (14 refs.)

• Research Organization: Florida Univ
• OSTI ID: 6574589
• Journal Information: AIChE J.; (United States), Journal Name: AIChE J.; (United States) Vol. 21:5; ISSN AICEA
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420400* -- Engineering-- Heat Transfer & Fluid Flow
DRAG
FLUIDS
FRICTION
MOLECULAR STRUCTURE
PH VALUE
POLYMERS
REYNOLDS NUMBER
VISCOSITY