NEW FORMULATION OF ACOUSTIC SCATTERING

Upon introducing the outgoing spherical (or circular cylinder) partial waves {⋔n} as a basis, the equation QT = â Re (Q) is obtained for the transition matrix T describing scattering for general incidence on a smooth object of arbitrary shape. Elements of Q involve integrals over the object surface, e.g. [formulla omitted]. where the â, + apply for Dirichlet and Neumann conditions, respectively. For quadric (separable) surfaces, Q is symmetric. Symmetry and unitarity lead to a secular equation defining eigenfunctions for general bodies. Some apparently new closed form results are obtained in the low frequency limit, and the transition matrix is computed numerically for the infinite strip. © 1969, Acoustical Society of America. All rights reserved.