Development of a PVDF sensor array for measurement of the impulsive pressure generated by cavitation bubble collapse

To study the impulsive pressure generated by cavitation bubble collapse, a PVDF piezoelectric array of pressure sensors is developed. The sensor array is fabricated directly on a 25 μm thick aluminum-metalized polarized PVDF film using a laser micro-machining technique. Dynamic calibration of the sensor array is accomplished in a gas shock tube. The average response time of the PVDF sensors to the fast-rising gas dynamic shock is found as fast as 31 ns. The array sensor is then attached on the solid boundary attacked by the collapse of the bubble. The features and the possible mechanisms of the impulsive pressure are discussed. The high sensitivity, low crosstalk, and low cost of the PVDF sensor array indicates its applicability in high amplitude impulsive field measurements.