WAVE EVOLUTION, REFLECTION, AND TRANSMISSION ALONG INHOMOGENEOUS WAVEGUIDES

✍ Scribed by R.S. LANGLEY

• Publisher: Elsevier Science
• Year: 1999
• Tongue: English
• Weight: 293 KB
• Volume: 227
• Category: Article
• ISSN: 0022-460X
• DOI: 10.1006/jsvi.1999.2337

✦ Synopsis

One-dimensional wave propagation along an inhomogeneous waveguide, such as an acoustic horn, a plate strip, a rod, or a beam is considered. The equations of motion of a generic waveguide are written in "rst order form, and the properties of the (position-dependent) eigenvalues and eigenvectors of the system are deduced by considering the symmetry and/or the energetics of the system. The equations of motion are then transformed to &&wave co-ordinates'' based on the right eigenvectors of the system, and a perturbation method is employed to study wave propagation along deterministic, periodic, and random waveguides. Attention is then turned to wave re#ection at a &&cut-o!' cross-section, and a general result for the phase of the re#ection coe$cient is derived. The general theory is illustrated by application to rod and beam examples. The method can be likened to a &&coupled modes'' approach in which the properties of the eigenvectors (or &&modes'') arising from symmetry and/or energetics are exploited.