Geometrical Aspects of Scattering and Physical Effects of Sound
Abstract
Research is reported primarily in the following areas: (1) High-frequency enhancements of the backscattering of sound by tilted (empty and water-filled) blunt elastic cylindrical shells in water are calculated and observed. The leaky-wave contributions to backscattering were studied and were also studied for a solid stainless-steel cylinder. A different type of backscattering enhancement was also studied for penetrable cylinders (e.g. plastics) supporting low-velocity waves. This enhancement is associated with a caustic-merging transition which was also confirmed with an analogous light scattering experiment. (2) The coupling of oscillating magnetic fields to the torsional modes of a stainless steel spherical shell in water was investigated. (Sound radiated by the magnetically excited modes is detected and resonances are identified.) (3) Some predicted properties of helicoidal ultrasonic waves were confirmed using a novel PVDF transducer. These waves have an axial null and have potential applications in scattering and alignment and they carry orbital angular momentum. Other research summarized concerns; (4) acoustical-scattering analogs studied with light; and (5) the acoustical probing of dilute aqueous suspensions of particles using radiation pressure.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 08, 1998
- Accession Number
- ADA361263
Entities
People
- Philip L Marston
Organizations
- Washington State University