Gas turbine engine component for acoustic attenuation

A gas turbine engine comprising:

• a fan section including a plurality of fan blades rotatable about an engine longitudinal axis;
• a compressor section that defines a core flow path, the compressor section including a first compressor and a second compressor downstream of the first compressor;
• a combustor section in fluid communication with the compressor section;
• a turbine section that drives the compressor section and the fan section;
• and
• wherein at least one of the compressor section and the turbine section includes a rotor assembly, the rotor assembly comprising:
• a rotor including a hub carrying a plurality of blades, the hub rotatable about the engine longitudinal axis, and a seal that extends outwardly from the hub to establish a sealing relationship with a plurality of vanes distributed about the engine longitudinal axis;
• and
• a flow guide assembly arranged about the longitudinal axis, the flow guide assembly secured to an engine static structure such that an annular flow path is defined between the hub and the flow guide assembly, the flow path including an inlet portion defined along the seal and an outlet portion, and the flow guide assembly including an acoustic liner that extends about the longitudinal axis to bound the flow path.

A method of sealing of a gas turbine engine, comprising:

• rotating a knife edge seal about an engine longitudinal axis, the knife edge seal including one or more knife edge portions supported by a neck portion, and the neck portion extending radially outward from a hub with respect to the engine longitudinal axis;
• communicating flow between a core flow path and an annular flow path, the flow path defined between the hub and a flow guide assembly such that the flow path slopes towards the engine longitudinal axis;
• and
• wherein the flow guide assembly includes an acoustic liner that extends about the longitudinal axis to bound the flow path.