Acoustic attenuation panel is made from moulded structural layer of resin-impregnated fibres and acoustic layer of microporous fabric

摘要

The panel, comprising a structural layer (2) with a reflective layer (3) on one side and an noise attenuating layer (1) on the other with acoustic (1b) and structural (1a) components, is made by forming the structural component of the noise attenuating layer in a mould from carbon, glass or other fibres, pre-impregnated with a thermoplastic or thermo-setting resin, using a process which creates a cellular structure with a 30 per cent open surface. This is covered by an acoustic layer (1b) of a microporous fabric of about a tenth of the thickness of the structural layer, made from fine carbon, glass or other fibres. The main cellular structural layer (2) and reflective layer (3) are then applied to the noise attenuating layer with adhesive (5, 6) between and the assembly is baked in an autoclave. The cellular structure of the noise attenuating layer's structural component can be made by spacing the fibres during a weaving or reeling process or by piercing it after b aking separately before assembly.