ASA 124th Meeting New Orleans 1992 October

5aPAa2. Scaling laws for sonoluminescence.

Ritva Lofstedt

Bradley P. Barber

Seth Putterman

Phys. Dept., Univ. of California, Los Angeles, CA 90024

The extremely nonlinear dynamics of bubble motion is described by the Navier--Stokes equations of fluid mechanics, as coupled to the laws of heat conduction and mass diffusion. In order to gain insight into the limitations of the hydrodynamic theory of bubble collapse, scaling laws have been derived for the maximum radius, collapse temperature, hot spot lifetime, collapse pressure, and ambient radius in terms of the applied sound field and the assumption that the bubble is a gas-filled cavity. In order to match the scaling laws to the experimental observations of collapse temperature and flash width requires that the Mach number for bubble motion exceed unity. In conclusion, a description of sonoluminescence must include the properties of imploding shock waves. [Work supported by the US DOE Division of Engineering and Geophysics; R. L. is supported by an A.T.&T. fellowship.]