Comparisons of backscattering from cylindrical shells described by thin shell and elasticity theories
Abstract
For kh less than or equal to 0.65, where k is the fluid wavenumber and h is the shell wall thickness, scattering from infinite cylindrical shells at normal incidence can be described by a combination of specular reflection and the zeroth order symmetric Lamb waves that correspond to extensional and inextensional modes of shell theory. LoveTimoshenko thin shell theory is found to closely describe the resonance scattering behavior from these types of structural modes. At higher values of kh, scattering from the antisymmetric Lambtype flexural modes is predicted by full elasticity theory. For materials in which the plate and modified shear wave speeds can be either greater or less than the wave speed in the backscattering predictions of fluid, the accuracy of LoveTimoshenko thin shell theory will be investigated near the excitation of the antisymmetric Lambtype flexural waves by comparisons with full elasticity theory. Plate theories will be used to develop a physical explanation of the resulting differences.
 Publication:

NASA STI/Recon Technical Report N
 Pub Date:
 March 1991
 Bibcode:
 1991STIN...9126475R
 Keywords:

 Backscattering;
 Cylindrical Shells;
 Elastic Cylinders;
 Resonance Scattering;
 Shear Properties;
 Structural Analysis;
 Thin Walled Shells;
 Elastic Waves;
 Lamb Waves;
 Plate Theory;
 S Waves;
 Shell Theory;
 Specular Reflection;
 Thick Walls;
 Fluid Mechanics and Heat Transfer