We have proposed a "micro-beam" MEMS sensor for measuring thermal conductivity of fluids, The principle of the measurement is to determine the thermal conductivity from the temperature rise of the sensor at a steady state, which is achieved within a millisecond. Promising application of the sensor includes the thermal conductivity detector (TCD) for gas detectors and gas chromatographs. However, these applications require the sensor to be used in the flow. We therefore placed the sensor in the core of the air flow from a nozzle,and examined the effect of air velocity on the temperature rise of the sensor.
