AN ACOUSTIC STUDY OF GASEOUS MICRO-BUBBLES IN BOUNDARY LAYERS AND PROPELLER WAKES
Abstract
Exploratory tests to measure the nature of the free gas which occurs in natural water due to the dynamic disturbance of a ship were conducted. Acoustic attenuation measurements serve to show that micro gas bubbles are evolved from dissolved gases by the shear dynamics of a boundary layer and that the rate of evolution increases as some function of the intensity and duration of the disturbance and of the pressure, viscosity, and gas content of the water. The tests conducted in the Laboratory, in large scale simulations of a ship's boundary layer and propeller, and in wakes of actual ship propellers. These exploratory tests indicate the need for more extensive tests in sea water under a wide variety of naval operating conditions. Such tests are necessary to a better determination of the role that these bubbles play in cavitation and acoustic detection problems.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1962
- Accession Number
- AD0406756
Entities
People
- John F. Ripken
- John M. Killen
Organizations
- University of Minnesota