Inproceedings,
Investigation of broadband characteristics of PVDF ultrasonictransducers by finite element modeling and experiments
Ultrasonics Symposium, 1999. Proceedings. 1999 IEEE, 2, page 1109-1112 vol.2. (1999)
DOI: 10.1109/ULTSYM.1999.849193
Abstract
FEM is a powerful tool when used interactively with experiments to
deduce the PVDF behavior under various boundary conditions. PVDF is a
soft, high damping, and high dielectric loss material whose tensor
properties are difficult to measure via standard testing methods. The
first part of this paper describes how FEM is used to determine and
refine some properties of the PVDF piezoelectric polymer which are
unknown or imprecisely provided by the manufacturer. The second part
addresses the broadband performance of a PVDF transducer constructed
with different layers of PVDF, and different backing configurations in
the frequency range from 10 kHz to 850 kHz. Because PVDF can be tailored
to special contoured shapes, directivity patterns with low sidelobe
level can be achieved which are difficult to obtain with a single
ceramic. For example, beam patterns with -30 dB side-lobes have been
achieved by canoe shaped transducers via `area shading'. Experimental
and predicted curves of transmit sensitivity, receive sensitivity,
bandwidth and directivity pattern for PVDF transducers with different
backings are shown
