DIRECTIVITY PATTERNS OF THE ACOUSTIC FIELD RADIATED FROM A SEMI-INFINITE UNFLANGED HARD WALLED CIRCULAR DUCTReport as inadecuate




DIRECTIVITY PATTERNS OF THE ACOUSTIC FIELD RADIATED FROM A SEMI-INFINITE UNFLANGED HARD WALLED CIRCULAR DUCT - Download this document for free, or read online. Document in PDF available to download.



Abstract : The theory of axi-symmetric wave that propagates to the duct outlet and radiates outside has been reviewed and applied to analyse the radiation characteristics in the far field. In general, the axi-symmetric wave that can propagate without damping along the semi-infinite hard walled duct is the superposition of all radial modes allowed at the fixed diffraction parameter. The mathematical tool used to obtain the results was the saddle point method applied to the exact formula for the velocity potential. The diffraction phenomena have been taken into account. Computed radiation characteristics of pressure and intensity directivity functions as well as power-gain function have been obtained for the diffraction parameter changing in the range 0-15. Some of the examples are presented on graphs.





Author: A. Snakowska

Source: https://hal.archives-ouvertes.fr/



DOWNLOAD PDF




Related documents