Accession Number : AD0681854

Title :   PROPELLER AND WAKE NOISE IN DEEP SEA SUBMERSIBLES. PART I. TRANSMISSION OF SOUND THROUGH A WIRE GAUZE IN STEADY FLOW,

Corporate Author : MASSACHUSETTS UNIV AMHERST SCHOOL OF ENGINEERING

Personal Author(s) : Carswell,C. C. ; Russell,G. A. ; Murthy,S. N. B.

Report Date : NOV 1968

Pagination or Media Count : 12

Abstract : The transmission of sound across a wire grid located cross-sectionally in a small tube carrying a low velocity flow is studied. A brief history of this and related problems is presented together with a technical justification for the present research. The physical arrangement of the wire grid and tube is presented and the assumptions necessary for writing linearized perturbation equations are discussed. The equations are given and a derivation of a subsequent equation involving the steady flow velocity, screen constant, acoustic frequency, and sound transmission coefficient is outlined. The interpretation of this equation in terms of the limiting case of no flow is discussed. Numerical solutions of the equation are presented and briefly interpreted in terms of air flow. An extension to the case of other flowing fluids is also outlined. Experimental results obtained to date are presented and some of the measurement problems are discussed. Plans for future analytical and experimental studies and possible applications for deep submersible vehicles are given. (Author)

Descriptors :   (*UNDERWATER SOUND, SOUND TRANSMISSION), FLUID FLOW, DEEP SUBMERGENCE, PROPELLER NOISE, WAKE

Subject Categories : Acoustics

Distribution Statement : APPROVED FOR PUBLIC RELEASE