On the tensile strength of water under pulsed dynamic stressing

We present experimental evidence to support a claim of Temperley and Trevena that, in the dynamic stressing of water by tension involving low–frequency ultrasound pulses, no serious discrepancy exists between theory and experiment. Experiments conducted on samples of deionized water suggest that this liquid can sustain a transient tension of up to ca.700 bar under dynamic stressing by pulses involving a stressing rate of ca.10 bar 𝛍s–1, in order–of–magnitude agreement with predictions of nucleation theory. In these experiments, tension pulses generated by the reflection of compressional waves from the free surface of a vertical column of water are found to propagate at a velocity appropriate to the vapour, where the amplitude of the pulses is sufficient to provoke cavitation of the liquid. Photographic evidence of this cavitation shows that it can occur in the body of the liquid, a feature of the experiments that, in addition to the high rate of stressing, may account for the relatively high values of tensile strength reported here.