Measurements of the Pressure Contours in Pressure Pulses Generated by Cavitation

A collapsing cavitation bubble emits a pressure pulse into the surrounding fluid. The temporal and spacial contours of such pulses are treated in the present paper. A schlieren observation method and an electroacoustic detection method with the aid of a suitable microphone are employed for this purpose. Cavitation was caused by sound in water at 21.6 kHz and 27 kHz. There results a maximum pressure of some 1 bar at a distance of 1 cm from the imploding bubbles. Cavitation traces observed on indium surfaces yield conclusions as to the acting maximum pressure which may amount to at least 10 000 bar.