Transient Radiation Loading of a Spherical Pulsed Sonar Array.
Abstract
The transient pressure on a spherical array arising from the excitation of a simple circular element has been obtained. The cases of a Heaviside step and a continuous wave (CW) pulse were considered. The low frequency, i.e., long time, response was obtained via a classical wave harmonic analysis. High frequency asymptotic expansions and the Watson transformation were used to isolate the short time transient effects into efficient 'creeping wave' series. Dispersion, caused by the spherical curvature, is shown to produce attenuation of the traveling wave and theoretically an exponentially decaying pulse of infinite duration. These creeping wave series are not valid in the immediate vicinity of, and on, the active element. However, in this region the Kirchhoff approximation has been shown to be applicable. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1970
- Accession Number
- ADA068877
Entities
People
- J. M. Garrelick
- M. C. Junger