Inertial cavitation threshold dependence on static pressures

A bubble will be nucleated in a liquid if the tension (or negative pressure) overcomes the forces that oppose the bubble's growth (static pressure and surface tension). The magnitude of the acoustic pressure required to nucleate a bubble capable of producing macroscopically measurable phenomena (e.g. light or shock waves) is the termed the inertial cavitation threshold. The hydrostatic pressure dependence of the inertial cavitation threshold in water was measured using standing waves in a spherical resonator. The resonator was driven at a radially symmetric mode with resonant frequency of 25.6 kHz at 1 atmosphere. The preliminary experimental measurements, reported here, showed the inertial cavitation threshold to be linear (r2= 0.98) over the range of static pressures measured, 10-250 bar. This is consistent with data reported for threshold reported at modest static pressures.