Optimisation of fireproof, pressurized acoustic sandwich structures

使用以轻质复合材料和铝为基础的材料，尽管在飞机的其他部件中很常见，但由于认证要求规定的耐火性，在发动机周围仍然是一个挑战。本项目的重点是使用这种材料制造涡扇飞机发动机的风扇壳体和旁路管道。这些部件有双重用途，第一是控制快速旁通流，第二是抑制发动机的声发射。这种部件通常由三层组成：承载大部分结构载荷的外层、蜂窝芯层和允许声能在芯层内消散的穿孔内层。因此，这种结构被称为声学夹层板。

The use of materials based on lightweight composite and aluminum, although common in other parts of the aircraft, remains a challenge around the engines because of the fire resistance prescribed by certification requirements. The present project focuses on the use of such materials for the manufacturing of fan cases and bypass ducts for turbofan aircraft engines. These components serve a dual purpose, the first is to contain the fast bypass flow and the second is to damp the acoustic emissions of the engine. Such components are typically an assembly of three layers: an outer skin that carries most of the structural load, a honeycomb core and a perforated inner skin that allows acoustic energy to be dissipated in the core. Accordingly, such constructions are called acoustic sandwich panels.