The critical modes of oscillation of a transversely inhomogeneous plate with a periodic structure

Ultrasonic scanning of an acoustic medium through a two-layer plate at the critical frequency

“…We In this case there are two other pairs of elementary solutions with a higher-power increase [4,7]. Note that the resonance modes do not transfer energy along the strip, since their specific energy flux through the transverse cross section of the strip, averaged over a period, is equal to To conclude this section we note that, for each resonance frequency, Eq.…”

“…A general theory of the definition of critical frequencies and the modes corresponding to them in the case when the elastic characteristics of the plate are arbitrary piecewise-continuous functions of the transverse coordinate has been given in [3,4]. The results described in these papers are obtained in a somewhat different form below for a two-layer strip, the faces of which are stress-free.…”

“…As a rule, the multiplicity is equal to 2, but for certain values of the parameters the multiplicity may be equal to 4 [4,7].…”