Review: MEMS sensors for flow separation detection

Flow separation is a critical aerodynamic phenomenon impacting flight envelope of various flying objects. Its efficient detection and subsequent control are vital for enhanced manoeuvring, better fuel economy, superior flight controls, and even for the survival of small air vehicles such as MAVs and UAVs. Over the past 3 decades, MEMS technology has enabled a paradigm shift from macro-level conventional sensing techniques to micro-scale sensors. Critical aerodynamics phenomenon such as flow separation, boundary-layer transitioning, shock, local flow and vortex dynamics, etc. can now be captured with better spatial as well as temporal resolution. Analysis spectrum has also been stretched by compensating the limitations of conventional techniques. This review paper is focused on the use of MEMS technology in the field of flow separation detection. We first briefly introduce the flow separation phenomenon and the limitations of conventional sensing techniques. Then, the application of MEMS to flow separation detection will be discussed in detail with emphasis on the prominent research work and performance review of various MEMS sensors employed in recent past.