The effect of polymer concentration on drag reduction

✍ Scribed by P.S. Virk; H. Baher

• Publisher: Elsevier Science
• Year: 1970
• Tongue: English
• Weight: 560 KB
• Volume: 25
• Category: Article
• ISSN: 0009-2509
• DOI: 10.1016/0009-2509(70)85008-4

✦ Synopsis

The effect of polymer concentration on drag reduction was studied experimentally with dilute distilled water solutions of a polyacrylamide and a polyethyleneoxide, molecular weights 4.7 and 1.3 x 1 OB respectively, in a 0~94.5 cm i.d. pipe. During drag reduction the polymer solutions obeyed friction factor relationships that were linear on semilogarithmic Prandtl-von Karman coordinates: the differente in slope between a polymer solution and the solvent was found proportional to the square root of polymer concentration over two decades of the latter. The square root relationship inferred from the present experiments was applied to and found to hold approximately for the results of other investigators for five different polymer-solvent_systems over concentration ranges of from one to three decades.