초록 ▼

An engine inlet sound diffusion structure for use with a turbofan engine is constructed of nonmetallic composite materials. An inner perforated skin of the diffuser is made up of continuously wound composite material filaments. A honeycomb core is sandwiched between the inner porous skin and a nonpo

An engine inlet sound diffusion structure for use with a turbofan engine is constructed of nonmetallic composite materials. An inner perforated skin of the diffuser is made up of continuously wound composite material filaments. A honeycomb core is sandwiched between the inner porous skin and a nonporous outer skin also comprised of continuously wound filaments. The perforations in the inner skin are formed directly in the skin by programmed placement of the filaments during the winding process. The formation of the perforations can be assisted by the use of a mandrel having spikes formed on its outer surface.

대표청구항 ▼

An acoustic treatment structure for use in the inlet of a turbofan engine formed by the process of filament winding an inner porous skin over a mandrel shaped to substantially conform to the inner shape of the turbofan inlet, said mandrel having pins protruding from the surface thereof, said pins be

An acoustic treatment structure for use in the inlet of a turbofan engine formed by the process of filament winding an inner porous skin over a mandrel shaped to substantially conform to the inner shape of the turbofan inlet, said mandrel having pins protruding from the surface thereof, said pins being of a length greater than the thickness of said inner skin, said filaments of said inner skin filling the spaces between said pins such that said inner sheet contains perforations corresponding to the locations of said pins upon removal from said mandrel, placing a preformed honeycomb core panel over said inner skin, said pins of said mandrel being of a length less than the thickness of said honeycomb core panel, and filament winding a nonporous outer skin over said honeycomb core panel while in place over said mandrel.