Stability and Decay Properties of Foam in Seawater.
Interim rept. Mar 84-Mar 86,
NAVAL RESEARCH LAB WASHINGTON DC
Pagination or Media Count:
Surface foam is formed by the entrainment of air in the form of small bubbles at and just beneath the water surface during white-capping, when steep waves break and when a displacement ship moves through the water. The residence time of a single-or multi-layer foam at the surface depends on the stability of the bubbles in that layer. This report presents the results of a study which examined the influence of salt content on the foaming ability of water and on the stability of a three-dimensional foam produced by blowing air through controlled laboratory samples of simulated sea water together with a sample of sea water obtained from an Atlantic coastal site. The results clearly show that varying the salt content of a clean water sample between 0 and 16 ppt. significantly influences its foaming ability and the corresponding stability of a layer of surface foam. For salinities between 16 and 36 ppt. there is no appreciable change in the foaming characteristics of a water sample. The behavior of the real seawater sample closely followed that of the simulated seawater samples. The stability characteristics of a multilayer surface foam are summarized in the report.
- Physical and Dynamic Oceanography