Abstract:
Evaporation and condensation provide a restoring force for the spherical oscillations of vapor bubbles. Unlike gas bubbles, the existence of this force is critically dependent on finite-rate processes, a fact that endows vapor bubbles with unusual properties such as two linear resonance frequencies. This paper extends the known linear results into the nonlinear domain by numerical simulation. The effects of forcing frequency, system pressure and temperature, and oscillation amplitude are studied. Particular attention is devoted to bubble behavior near the anomalous second resonance. The motivation for this work is offered by the possibility of using pressure radiation forces to remove boiling bubbles from hot surfaces in microgravity. [Work supported by the National Aeronautics and Space Administration.]