Interfacial tension and acoustofluidics: some connections, instabilities, experimental results, and theory

Abstract

It is timely to examine early acoustofluidic studies involving surface tension phenomena. The dynamics of fluid cylinders and the Plateau-Maxwell-Rayleigh interfacial instability have been reviewed [P. L. Marston, Phys. Fluids 29, 029101 (2017)]. Here, some related acoustofluidic experiments on liquid cylinders are noted [S. F. Morse et al., Phys. Fluids 8, 3 (1996); M. J. Marr-Lyon et al., Phys. Rev. Lett. 86, 2293 (2001)]. Those were after modulated radiation pressure investigations of the shape dynamics of levitated drops and bubbles [P. L. Marston, J. Quant. Spectrosc. Radiat. Transfer 254, 107226 (2020)]. Especially noteworthy are the subtleties of acoustically trapping and deforming bubbles in water larger than the size for monopole resonance [T. J. Asaki, P. L. Marston, and E. H. Trinh, J. Acoust. Soc. Am. 93, 706 (1993)]. That ability facilitated a series of measurements of bubble interfacial dynamics and shape [Asaki et al., J. Acoust. Soc. Am. (1994-1997); J. Fluid Mech. (1995); Phys. Rev. Lett. (1995)]. A related discussion of the quadrupole projection of the radiation stress is noteworthy [P. L. Marston, Phys. Rev. E 100, 057001 (2019)] along with early publications reporting the break-up of drops and bubbles in water through the application of modulated acoustic radiation forces.