Sound absorbing composite structure for marine craft, e.g. submarines - has damping layer clamped by bolts between a cover layer with projections and a carrier layer

摘要

Composite comprises a damping layer (13) clamped by bolts (12) between a cover layer (14) and a carrier layer (10). The boundary between the cover layer (14) and the damping layer (13) has projections. The projections can be confined to either the damping layer (13) or the cover layer (14). The cover layer (14) can be cast in epoxy resin with hollow glass beads and have conical projections. A viscoelastic damping layer (13) is clamped by bolts (12) between a carrier sheet (10) and a cover sheet (14). The damping layer (13) and carrier sheet (10) have similar thickness, e.g. 30 mm. Unevenness (15) up to 5mm in the carrier plate (10) is taken up as the approximate 10 mm high projections are pressed into the damping layer (13). USE/ADVANTAGE - The invention is used for acoustic components on submarine hulls which can be disassembled for repair.