A micro flow sensor from a polymer for gases and liquids

In this paper, we present a micro flow sensor from a polymer based on the thermal anemometric principle. A sensor with outer dimensions of 5.5 × 6 × 1.2 mm 3 and a small fluidic channel with a cross-section of 240 µm × 400 µm may be operated with both gases (up to 200 ml min −1 ) and liquids (for water up to 200 µl min −1 ). Due to its small heat capacity, the sensor is also suitable for dynamical measurements of liquid flows, e.g. flow pulsations up to several 100 Hz even within high-pressure hydraulic systems.