Abstract
The frequency characteristics and the input impedance of cavity-mounted pressure sensing systems have been derived by considering the tube impedance and the radiation impedance as well as the orifice resistance across the sensing hole. The system can be modeled as a L-R-C series circuit with the resistance affected by signal frequency and amplitude. The theoretical result has a good agreement with the experimental one for wide ranges of geometrical and signal parameters.
It is clarified that a smaller cavity volume and a larger sensing hole can realize a wider frequency band, a higher input impedance (smaller modification of flow), and a smaller nonlinearity.
