Dynamic Coupling Coefficients for DisTRIBUTED Parameter Piezoelectric Transducers

摘要

This report discusses a definition of the effective coupling coefficient for the body-force class of electromechanical transducers. This definition is based on the distribution of energy in the transducer and is therefore particularly applicable to the 'distributed parameter' type of transducer. Furthermore, the definition results in a frequency dependent coupling coefficient which is valid for all modes of vibration. The definition is applied to some common types of longitudinal vibrator and the results are compared with experiments for one particular device (a partially excited stack of ceramic disks). The influence of parasitic elements on the system coupling is also examined.