DUCTED AIR SYSTEM WITH SYNTACTIC MATERIAL PLACED ADJACENT AN OUTLET FOR NOISE ATTENUATION AND ASSOCIATED METHOD

摘要

A ducted air system such as provided in buildings and water borne vessels for heating, ventilating or air conditioning and wherein noise reduction is effected by the provision within a walled duct (10) through which the airstream (11) passes, of a syntactic composite material (12) through which a substantial portion of the volume of said airstream is constrained to flow before exiting the duct. The material (12), being of particulate form causes the airstream to flow through the interstices between the particles of the material thus assisting in the absorption of noise generated within the system.