Air system for aircraft powerplant

An assembly for an aircraft powerplant, comprising:

• a compressor rotor configured to rotate about an axis, the compressor rotor including a rotor stage and a rotor hub, the rotor stage including a rotor base and a plurality of compressor blades connected to the rotor base, the plurality of compressor blades arranged circumferentially about the rotor base in a compressor blade array, the rotor hub including a seal element and a hub wall connected to the rotor base, the hub wall tapering radially inward towards the axis as the hub wall projects axially away from the rotor base, the seal element projecting radially out from the hub wall, and the rotor hub forming a peripheral boundary of an air passage;
• a compressor vane structure axially next to the rotor stage and radially outboard of the hub wall, the compressor vane structure comprising a seal land and a plurality of compressor vanes arranged circumferentially about the axis in a compressor vane array, the seal land radially outboard of and configured to form a seal with the seal element;
• a core flowpath extending longitudinally across the plurality of compressor blades and through the compressor vane structure;
• and
• an air system including an air circuit and a heat exchanger, the air circuit extending longitudinally from a circuit inlet through the heat exchanger to a circuit outlet, and the air system configured to bleed compressed air from the core flowpath downstream of the rotor stage through the circuit inlet, cool the compressed air with the heat exchanger to provide cooled air, and direct the cooled air into the air passage through the circuit outlet in an axial direction towards the seal element.

An assembly for an aircraft powerplant, comprising:

• a compressor rotor configured to rotate about an axis, the compressor rotor including a rotor stage and a rotor hub, the rotor stage including a rotor base and a plurality of compressor blades connected to the rotor base, the plurality of compressor blades arranged circumferentially about the rotor base in a compressor blade array, the rotor hub comprising a hub wall connected to the rotor base, the hub wall tapering radially inward towards the axis as the hub wall projects axially away from the rotor base, and the hub wall forming an inner peripheral boundary of at least a first section of an air passage;
• a compressor vane structure axially next to the rotor stage and radially outboard of the hub wall;
• a diffuser structure including a diffuser nozzle and a diffuser plenum, the diffuser nozzle radially outboard of the hub wall;
• a combustor disposed in the diffuser plenum;
• a core flowpath extending longitudinally across the plurality of compressor blades and through the compressor vane structure, the diffuser nozzle and the diffuser plenum into the combustor;
• a baffle wall mounted to the diffuser structure, the baffle wall following a contour of the rotor hub and forming an outer peripheral boundary of at least the first section of the air passage, wherein an air cavity is disposed radially and/or axially between the baffle wall and the diffuser structure;
• and
• an air system including an air circuit and a heat exchanger, the air circuit extending longitudinally from a circuit inlet through the heat exchanger to a circuit outlet, and the air system configured to bleed compressed air from the core flowpath through the circuit inlet, cool the compressed air with the heat exchanger to provide cooled air, and direct the cooled air into the air passage through the circuit outlet in an axial direction towards a seal element, the seal element forming an axial boundary of the air passage.