X
X’
Y
q
q
j
Z
3-18
Singly Rotated and Doubly Rotated Cuts’
Vibrational Displacements
Vibrational Displacements
Singly rotated
resonator
Doubly rotated
resonator
| In a vibrating doubly rotated resonator ( 35° and
>
0°),
the displacement is partly out of the plane of the plate, as is illustrated.
By controlling the -angle, one may control the ratio of in-plane to
out-of-plane displacements. |
|
| A sensor for sensing the properties of a
fluid has been proposed based on this.
In a fluid, the out-of-plane component of the displacement propagates
a damped compressional wave, while the in-plane component propagates a damped
shear wave. The frequency changes of doubly rotated resonators have been
measured in glycerol solutions of a variety of concentrations. At each
concentration, the frequency change was found to increase with increasing phi-angle. |
|
| -------------------------- |
|
| Y. Kim,
J. R. Vig and A. Ballato, “Sensing the properties of liquids with doubly
rotated resonators,” Proc. 1998 IEEE Int’l Frequency Control Symp., 1998, pp.
660-666. |
|