### ASA 128th Meeting - Austin, Texas - 1994 Nov 28 .. Dec 02

## 2pPAa8. Compressibility in bubble dynamics and scattering.

**Paul E. Barbone
**

**
Ali Nadim
**

**
Daniel Goldman
**

**
**
*Dept. of Aerospace and Mech. Eng., 110 Cummington St., Boston Univ.,
Boston, MA 02215
*

*
*
The Rayleigh--Plesset equation describes the oscillations of a spherical
bubble wall under the assumption that the fluid surrounding the bubble is
incompressible. Many modifications of this equation have been proposed to
incorporate slight fluid compressibility, and though different in form, they
are asymptotically equivalent. The different forms of the equations, however,
reveal remarkably different properties. In some forms of the modified
Rayleigh--Plesset equation, for example, spurious unstable solutions are
present while in other cases they are not. Here, physically motivated
restrictions on the form of the modified Rayleigh--Plesset equation are
discussed. These restrictions are discussed in the context of causality
requirements and higher-order corrections to the modified Rayleigh--Plesset
equation.