Sound Radiated by Spheres Falling in Poly (Ethylene Oxide) Solutions.
Abstract
Sound radiated by spheres freely falling in aqueous solutions of poly(ethylene oxide) at concentrations 0 and 100 wppm was investigated. In solution of 0 wppm concentration, only those spheres with calculated Reynolds numbers (based on the terminal speed) at or above the critical value radiated sufficient energy to be detected above the background. This sound consisted of frequent, distinct noise bursts. In the 100 wppm solution, all spheres with Reynolds numbers near the critical value displayed an increase in speed and a reduction of radiant sound to below background. The one sphere definitely in the supercritical region did not significantly change in speed, and the radiant sound was not reduced as much as for the other spheres. These observations are consistent with the assumption that the noise bursts are produced in the wake associated with laminar separation, and with the previous observation that polymer addition shifts the critical Reynolds number to higher values. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1968
- Accession Number
- AD0847671
Entities
People
- Joseph Michael Sendek
Organizations
- Naval Postgraduate School