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International audience; In aeronautic sector, the reattachement of separeted air flows close to aircraft wings can be actively controlled by blowing air jets in the boundary layer, through submillimetric holes situated on airplane wings near the seperation edges. Performance improvement of next generation planes (lift enhancement, drag reduction) pushes plane designers to investigate MEMS solutions in order to provide active air flow control. This paper presents realization of silicon cantilever beams by Deep Reactive Ion Etching (DRIE) in order to reach high aspect ratio. These cantilever beams take place in the design and realization of a micro-valve which will provide high speed pulsated air jets for boundary layer control.

International audience; Aeraulic flow control constitutes an important stake in the transport sector and especially in aeronautics. It allows a consequent energetic savings. Fluidic Microsystems are the perfect candidates to decrease the fuel consumption and sound pollution. These microsystems are intended to act on aircraft aerodynamic performances by controlling the trailing air-flows of aircraft flaps on the boundary layer. This work presents the design and the manufacture of an electrostatic micro-valve. The purpose of this device is shift the boundary layer separation point by transferring momentum energy via high speed pulse micro air jets. The device is based on a pair of rigid electrodes and a S-shaped flexible ribbon. It can provide local high electrostatic forces required to control rather large pressures. This kind of micro-actuators is called “Zip” actuators. It can act efficiently on the boundary layer control by modulating pressures. We will present finite elements simulations with the software Ansys They validate the dimensioning of our prototype and show that it can control pressures up to 1 bar upstream a 45° skew, 400 μm diameter orifice. For this maximum pressure, the corresponding velocity is close to 170 m/s. We will also present the clean-room process we developed to manufacture this micro-valve.