Rayleigh-Plesset equation

In fluid mechanics, the Rayleigh–Plesset equation is an ordinary differential equation which governs the dynamics of a spherical bubble in an infinite body of liquid. Its general form is usually written as

where

Provided that ${\displaystyle P_{B}(t)}$ is known and ${\displaystyle P_{\infty }(t)}$ is given, the Rayleigh–Plesset equation can be used to solve for the time-varying bubble radius ${\displaystyle R(t)}$.

...
Wikipedia