In this thesis, a review is given of the development of the theory and experimental work on acoustic wave propagation in water containing air bubbles. Then: the various processes of attenuation of sound for distributions of air bubbles in a liquid, which are regarded as simulating the properties of foams, are considered theoretically by the author. The measurements of the attenuation of sound in air-liquid foams, whose parent liquids have viscosities in the range 1-10 centipoise, show an order of magnitude agreement with a theory which suggests that the attenuation is due to viscous dissipation in the bubble walls. The possibility of energy loss due to pressure relaxation in an atmosphere of saturated vapour is rather discounted by the smallness of the calculated value as compared with the overall measured attenuation. The measured values of the velocity of sound in air-liquid foams, for those with very large volume air concentrations, lie in the neighbourhood of the computed adiabatic values. This contrasts with the measurements of Karplus(14) in water containing air bubbles, of lower volume air concentrations, which agreed well with computed values for the isothermal velocity of sound.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:623039 |
| Date | January 1968 |
| Creators | Hay, Bridget |
| Publisher | Imperial College London |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://hdl.handle.net/10044/1/15860 |
Page generated in 0.0022 seconds