Heat transfer in sound propagation and attenuation through gas–liquid polyhedral foams

Abstract

A cell method is developed, which takes into account the bubble geometry of polyhedral foams, and provides for the generalized Rayleigh-Plesset equation that contains the non-local in time term corresponding to heat relaxation. The Rayleigh-Plesset equation together with the equations of mass and momentum balances for an effective single-phase inviscid fluid yield a model for foam acoustics. The present calculations reconcile observed sound velocity and attenuation with those predicted using the assumption that thermal dissipation is the dominant damping mechanism in a range of foam expansions and sound excitation frequencies.

Wind–wave stabilization by a foam layer between the atmosphere and the ocean

“…It should be additionally note that accounting for non-Newtonian effects of the foam, which occur due to foam bubbles oscillations (see e.g. Shtemler and Shreiber, 2006) and ignored in the present study, will additionally stabilize the water surface compared with the two-fluid air-water system.…”

“…The foam compressibility may be ignored within the same accuracy as that of the air. Indeed, using the smallness of Mach number M a = U a /C a for air and noting that the foam-to-air sound velocity ratio (Shtemler and Shreiber, 2006) is of the same order as ε / a f U U (see Eqs.…”