Air circuit for aircraft propulsion system

1 . An assembly for an aircraft propulsion system, comprising:

a core flowpath extending axially along an axis;

a bypass flowpath radially outboard of the core flowpath, the bypass flowpath extending axially along the axis;

a flowpath wall forming an inner peripheral boundary of the bypass flowpath, the flowpath wall extending axially along and circumferentially about the axis;

an ejector body disposed in the bypass flowpath, the ejector body spaced radially outboard from the flowpath wall by a first distance such that a portion of the flowpath radially between the ejector body and the flowpath wall forms an ejector passage, and the ejector passage extending axially along the axis from a passage inlet to a passage outlet; and

an air circuit extending from a circuit inlet to a circuit outlet, the circuit inlet fluidly coupled to the core flowpath, and the circuit outlet fluidly coupled to the bypass flowpath at the passage outlet,

wherein the ejector passage is configured to accelerate a flow of bypass air to draw bleed air out of the air circuit.

2 . The assembly of claim 1 , wherein the circuit outlet is downstream of the passage outlet along the bypass flowpath.

3 . The assembly of claim 1 , wherein the first distance between the ejector body and the flowpath wall decreases as the ejector passage extends from the passage inlet towards the passage outlet.

4 . The assembly of claim 1 , wherein the first distance between the ejector body and the flowpath wall remains uniform as the ejector passage extends from the passage outlet towards the passage inlet.

5 . The assembly of claim 1 , wherein a thickness of the ejector body decreases as the ejector passage extends to the passage inlet.

6 . The assembly of claim 1 , wherein a thickness of the ejector body decreases as the ejector passage extends to the passage outlet.

7 . The assembly of claim 1 , wherein

the ejector body is spaced radially inboard from an outer peripheral boundary of the bypass flowpath by a second distance; and

the second distance is equal to or greater than five times the first distance.

8 . The assembly of claim 1 , wherein

the air circuit is configured to direct air, bled from the core flowpath through the circuit inlet, along a trajectory through the circuit outlet into the bypass flowpath; and

the trajectory has an axial component pointing axially away from the ejector body.

9 . The assembly of claim 8 , wherein the trajectory further has a circumferential component.

10 . The assembly of claim 1 , wherein the ejector body extends at least thirty degrees circumferentially about the axis.

11 . The assembly of claim 1 , wherein the ejector body extends at least forty-five degrees circumferentially about the axis.

12 . The assembly of claim 1 , wherein the ejector body extends circumferentially about the axis between opposing circumferential protrusion ends.

13 . The assembly of claim 1 , wherein the ejector body circumscribes the flowpath wall.

14 . The assembly of claim 1 , further comprising:

a compressor section comprising a first compressor rotor and a second compressor rotor, the first compressor rotor upstream of the second compressor rotor along the core flowpath;

the core flowpath extending through the compressor section;

the bypass flowpath bypassing the compressor section; and

the circuit inlet fluidly coupled to the core flowpath upstream of the second compressor rotor.

15 . The assembly of claim 14 , wherein the circuit inlet is disposed between the first compressor rotor and the second compressor rotor along the core flowpath.

16 . The assembly of claim 14 , wherein the circuit inlet is disposed along the first compressor rotor.

17 . The assembly of claim 1 , further comprising a plurality of guide vanes disposed in the bypass flowpath upstream of the ejector body.

18 . The assembly of claim 1 , further comprising:

a fan rotor rotatable about the axis;

an airflow inlet into the core flowpath and an airflow inlet into the bypass flowpath next to and downstream of the fan rotor.

19 . An assembly for an aircraft propulsion system, comprising:

a flowpath extending axially along an axis;

a flowpath wall forming an inner peripheral boundary of the flowpath, the flowpath wall extending axially along and circumferentially about the axis;

an ejector body spaced radially outboard from the flowpath wall such that an ejector passage is formed by and disposed radially between the ejector body and the flowpath wall, the ejector passage extending axially along the axis from a passage inlet to a passage outlet;

an air circuit extending from a circuit inlet to a circuit outlet, the circuit outlet fluidly coupled to the flowpath next to and downstream of the passage outlet; and

an air source fluidly coupled to the circuit inlet,

wherein the ejector passage is configured to accelerate a flow of bypass air to draw bleed air out of the air circuit.

20 . An assembly for an aircraft propulsion system, comprising:

a flowpath extending axially along an axis;

a flowpath wall forming an inner peripheral boundary of the flowpath, the flowpath wall extending axially along and circumferentially about the axis;

an ejector body disposed radially outboard of and extending circumferentially about the flowpath wall;

an ejector passage formed by and disposed radially between the ejector body and the flowpath wall, the ejector passage extending axially along the axis from a passage inlet to a passage outlet;

an air circuit extending from a circuit inlet to a circuit outlet, the circuit outlet fluidly coupled to the flowpath downstream of the passage outlet; and

an air source fluidly coupled to the circuit inlet,

wherein the ejector passage is configured to accelerate a flow of bypass air to draw bleed air out of the air circuit.