Direct measurement technique of wall shear stress using MEMS sensors in a high-speed wind tunnel

This paper presents a direct measurement technique for wall shear stress.The capacitive MEMS sensor with pectinate floating element Was developed.The techniques of static and dynamic calibration are in-troduced.The demonstrative experiment wag carried out in a high-speed wind tunnel.The experiment results in-dicate that the local shear stress in turbulent flow is noticeably higher than in laminar flow.Monitoring localshear stress on a model can be also used for determining transition zone.In the present experiment,the transi-tion zone detected by the MEMS sensor is identical with what by the pressure transducer.