A MEMS skin-friction sensor for time resolved measurements in separated flows

摘要

A MEMS surface fence sensor for skin-friction measurements in separated flows has been developed and tested successfully in low-speed flows. The new sensor is able to distinguish between forward and reverse flow and features a temporal resolution of up to 1 kHz. Calibrations of the sensor have been obtained in the range of -0.7 N m(-2)less than or equal totau(w)less than or equal to0.7 N m(-2) with a resolution of 0.02 N m(-2). Comparative measurements with the wall-pulsed wire technique in a reverse-flow region show excellent agreement with respect to the mean skin-friction coefficient c(f) but also reveal some discrepancies for the fluctuating part c(f)'.