The development of a new acoustic sensor makes it possible to measure acoustic particle velocity instead of sound pressure. The new sensor, called the Microflown, can be used in the frequency range of 0 to approximately 20 kHz. As one of the first applications, the new sensors are applied in an impedance tube to determine the impedance of an aluminium sample at the end of the tube. The sample has an orifice which accounts for the sound absorption. Comparing the results with theory and measurements with microphones leads to an excellent agreement. The characteristics of the Microflowns, like the simplicity and the small dimensions, make it a very attractive alternative to the microphones. Furthermore, the sensitivity to the direction of the acoustic waves and the matching of the phase and sensitivity of two sensors can be used in other research fields in acoustics as well.
- Acoustic sensors
- Acoustic impedance measurement
- Acoustic flow
van der Eerden, F. J. M., de Bree, H. E., & Tijdeman, H. (1998). Experiments with a new acoustic particle velocity sensor in an impedance tube. Sensors and actuators. A: Physical, 69(2), 126-133. https://doi.org/10.1016/S0924-4247(98)00070-3