Shear Stress Measurements on an Airfoil Surface Using Micro-Machined Sensors

Abstract

The motivation for this research was to obtain information on the separation characteristics associated with the phenomenon of stall. This separation data will ultimately be utilized as part of an optimum control system to reduce the negative effects associated with stall. Surface shear stress measurements were carried out using MEMS-based sensors on a two-dimensional wing with a Wortmann FX 63-137 airfoil section(chord Reynolds numbers ranged from 1×10⁵ to 6×10⁵). Computational airfoil performance from an airfoil analysis code was compared with the results of measurements. The wall shear stress distribution was measured by five micro hot-film sensors, which were flush mounted on the 2-D wing over the frontal 50% of the chord at various spanwise locations. Hysteresis characteristics were determined from time-averaged and rms shear stress values as well as from airfoil performance curves.