GROWTH OF A VAPOR BUBBLE IN AN ULTRASONIC FIELD.

The growth of a vapor bubble in a small-amplitude ultrasonic field is analyzed. It is shown that bubble growth is caused mainly by the absorption of ultrasonic mechanical energy due to evaporation and condensation of the liquid at the boundary of the bubble. An expression is derived for the rate of change of the bubble radius in an ultrasonic field; it is shown that this rate does not depend on the radius. Numerical estimates are given for the growth rate of vapor bubbles in liquid hydrogen and in water.