TECHNICAL FIELD

The present disclosure relates to composite liners for gas turbine engines.

BACKGROUND

Gas turbine engines used to propel vehicles, e.g., aircraft, often include a fan assembly or propeller that is driven by an engine core. In a fan assembly, the fan blows air to provide part of the thrust for moving the aircraft. Fan assemblies typically include a bladed wheel mounted to a shaft coupled to the engine core. The bladed wheel of the fan assembly may include a plurality of airfoils in the form of fan blades coupled to a fan disc. In some examples, gas turbine engines may also include airfoils in the form of circumferentially spaced radially extending outlet guide vanes (OGVs) located aft of the bladed wheel. Gas turbine engine also include a fan case that surrounds the fan assembly. An inner surface of the fan case defines an outer wall of the bypass flow path. Proceeding from the front toward the back of the fan case, the inner surface may include front acoustic panels (FAP), fan track liners (FTL), ice impact panels (IIP), and rear acoustic panels (RAP).

SUMMARY

The disclosure describes composite liners for fan cases of turbofan engines and techniques for forming composite liners. A composite liner as described herein may include a body formed from a composite material, which includes a matrix material, relatively tough polymer-based reinforcement elements, and second reinforcement elements. Such composite liners may be relatively lightweight, yet tough (e.g., reduced brittleness) to increase resistance to fracturing or provide selective sections more prone to fracture when struck by a objects, including birds, ice, fan blades, or the like.

In some examples, the disclosure describes a composite liner that includes at least one region comprising a reinforcement architecture comprising a matrix material, a plurality of relatively tough polymer-based reinforcement elements, and a plurality of second reinforcement elements. The plurality of relatively tough polymer-based reinforcement elements and the plurality of second reinforcement elements are embedded in the matrix material

The details of one or more examples are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description and drawings, and from the claims.

