Accession Number : AD0738511

Title :   On the Transmission of Sound Waves through a Blade Row,

Corporate Author : DEUTSCHE FORSCHUNGS- UND VERSUCHSANSTALT FUER LUFT- UND RAUMFAHRT E V AACHEN (WEST GERMANY)

Personal Author(s) : Koch,W.

Report Date : 25 MAR 1971

Pagination or Media Count : 19

Abstract : The problem of the transmission and reflection of plane sound waves incident upon a single cascade of finite plates is solved by means of the finite Wiener-Hopf technique. The results are given in explicit form containing an infinite number of constants. These constants, which are related to the attenuated waves in the duct formed by two adjacent blades, have to be determined from an infinite system of linear, algebraic equations. An iterative solution is possible and converges rapidly in most cases. But even without taking these attenuated modes into account (equivalent to a zeroth approximation) good agreement with previous results is obtained. In their simplest form, the final formulas reduce to the ones give by Mani and Horvay. (Author)

Descriptors :   (*SOUND TRANSMISSION, BOUNDARY VALUE PROBLEMS), (*JET ENGINE NOISE, REDUCTION), PARTIAL DIFFERENTIAL EQUATIONS, INTEGRAL EQUATIONS, SUBSONIC FLOW, BLADE AIRFOILS, NUMERICAL ANALYSIS, WEST GERMANY

Subject Categories : Numerical Mathematics
      Acoustics

Distribution Statement : APPROVED FOR PUBLIC RELEASE