Determination of the sensitivity behaviour of an acoustic and thermal flow sensor by electronic characterisation

The Microflown is an acoustic and thermal flow sensor that measures the sound particle velocity instead of sound pressure. For most applications the Microflown should be calibrated, which is usually performed acoustically in a standing-wave-tube. Here it is shown that the sensor´s sensitivity and frequency behaviour can be determined electronically as well, and an electronic method for determination of the device output response, which is more convenient, is therefore presented. The method is not only less complicated, it also makes it possible to cover easily the entire acoustic frequency spectrum.