Drag measurements on a thin plate in dilute polymer solutions

Abstract

Drag measurements were made by towing a thin plate (a plate with a 3-ft chord) in plain water and in dilute solutions of Polyox WSR-301, over a Reynolds-number range between $3\times {10}^6$ and $1\times {10}^7$ . These tests were performed in Aerojet’s ring channel. Samples of these solutions were also tested in a pipe-friction apparatus at the U.S. Naval Ordnance Test Station, Pasadena.

Results of the test with the plate show a reduction in drag of 33% with a Polyox concentration of 1.5 wppm, and a maximum reduction of 63% with concentrations of 15 to 20 wppm. With higher concentrations (up to 100 wppm), the drag reduction was somewhat less than this maximum. There is evidence that the effectiveness of these solutions for reducing drag was diminished with passage of time after preparation of the solutions. Also, it appeared that there was some instability in the flow over the plate.