Aero-Micro-Electromechanical System Sensor Arrays for Time Resolved Wall Pressure Measurements

Abstract

Wall pressure and wall pressure fluctuations in turbulent flows are of interest in many engineering applications. This paper focuses on the design and fabrication of aero-micro-electromechanical system surface pressure sensor arrays and their application to wall pressure measurements on a wall-mounted cylinder. The sensor arrays have been developed to be highly sensitive and mounted flush with the measurement surface. Thus, dynamic properties of the sensors are not limited by tubing, and an accurate measurement of the wall pressure and its fluctuations becomes possible. The arrays introduced herein consist of a number of individual sensors, which feature a maximum sensitivity of 12 μV/(VPa) and a pressure resolution of up to 0.5 Pa. Employing six arrays (three different types) consisting of up to 13 individual pressure sensors, wall pressure measurements have been conducted at the University of Rostock at a Reynolds number of 200,000. The results prove that the developed sensor arrays are a powerful measurement tool for experimental fluid mechanics. The wall pressure measurement data obtained are in good agreement with the results of the laser Doppler anemometry measurements and large-eddy simulations, which are also presented herein.