WAVE MIXING EFFECTS ON A PERIODICALLY RIBBED CYLINDRICAL-SHELL

An examination of the response of a periodically ribbed cylindrical sh ell shows several effects die to the mixing of fast and slow waves on the shell. In wavenumber-frequency space, this mixing manifests itself in the formation of hybrid modes, for example, mixtures of part shear and part flexural vibration. The mixing is strongest when the phase s peeds of the different wave types coincide find so reflect the dispers ion curves of the flexural Bloch wavenumber. The dispersion curves may be significantly altered by mixing effects, and even for weak wave mi xing the polarization of the fast waves can be changed significantly. This effect greatly alters the coupling of the fast waves to an extern al fluid.