Development of an array of pressure sensors with PVDF film

Abstract

A new type of an array of pressure sensors, composed of PVDF (polyvinylidenefluoride), was devised and evaluated. In order to obtain the system transfer function of the PVDF system, a dynamic calibration was performed utilizing the signal from a 1/8 inch B&K microphone as input. The time history of the unsteady pressure was then reconstructed from the output of the sensor by using this transfer function. The reconstructed pressure signals showed good agreement with the reference signal in both temporal and spectral sense. This sensor was then used to measure the wall pressure fluctuations in a two-dimensional turbulent channel flow. Various statistical moments were obtained from the measurement data set. Comparison of these quantities with the existing studies demonstrated satisfactory agreement. These tests give credence to the relevance and reliability of this sensor for applications in more complicated turbulent flows.