Table 1.
Peak negative and positive pressures and pulse-average intensities measured at the focal point of the transducer in water for the range of exposure level used in the experiments and for both types of excitations.
| Peak pressures | Spatial-peak pulse-average intensity | Total acoustic power | |
|---|---|---|---|
| p − (MPa) | p + (MPa) | I sppa (W/cm2)a | P ac (W) |
| Monofrequency excitation | |||
| 3 | 3.6 | 360 | 50 |
| 4.2 | 6.2 | 770 | 110 |
| 5.2 | 8 | 1200 | 165 |
| 5.5 | 9.0 | — | 220 |
|
| |||
| Bifrequency excitation | |||
| 5 | 7 | 510 | 70 |
| 6 | 9 | 750 | 110 |
| 6.5 | 10.5 | ~1000a | 150 |
| 7.5 | 12.5 | — | 220 |
aIntensities are estimated by integrating waveforms recorded at the focal point. At P ac = 220 W, occurrence of cavitation prevents from giving an accurate estimation of the intensity. Bifrequency waveform at P ac = 150 W was also perturbed by cavitation.