A flexible micromachine-based shear-stress sensor array and its application to separation-point detection

A new microfabrication technique has evolved and has been applied to the de velopment of a flexible shear-stress sensor array. The flexible sensor arra y is composed of many silicon islands that an interconnected by two layers of polyimide film. The silicon islands are formed by RIE etching and contai n individual thermal shear-stress sensors. Each sensor on the flexible sens or array has been proven to behave the same as those on a rigid substrate. There are more than 100 sensors distributed inside a I cm x 3 cm area. The flexible sensor array has a thickness of 80 mu m and can be easily attached on a highly curved surface to detect shear-stress distribution. Applicatio ns of the flexible sensor array to flow separation-point detection have bee n demonstrated in this task including flow over a circular cylinder and ins tantaneous separation line detection on the rounded leading edges of a delt a wing. (C) 2000 Elsevier Science S.A. All rights reserved.