Sound Propagation in Bubbly Liquids. A Review
Memorandum rept. Jun-Aug 1988
NAVAL RESEARCH LAB WASHINGTON DC
Pagination or Media Count:
This report considers the propagation of plane sound waves in a liquid containing a homogeneous distribution of small, nondiffusing gas bubbles. We have concentrated on the basic theories of Wood and Kennard for phase speed in equilibrium conditions, and at finite frequencies, respectively. A derivation of phase speed from first principles indicates the Woods equation is an accurate approximation for dilute mixtures of gas bubbles in a liquid. The conditions under which Woods equation does not apply are discussed based on the analytic expressions obtained from the fundamental derivation. Kennards equation is based on assumptions which have not been critically examined, particularly in regard to the compressibility model on which is based, and on the frequency dependence of the relevant damping coefficients. Keywords Sound speed Bubbly liquids Woods equation Two phase media.