Propulsion engine thermal management system

1. A propulsion engine for an aeronautical vehicle defining a radial direction and an air flowpath, the propulsion engine comprising:

an electrical power source positioned within a casing, the air flowpath being partially defined within the casing; and

a fan comprising a fan blade rotatable by the electrical power source and extending generally along the radial direction, the fan blade defining an inlet, an outlet, and an air passage extending between the inlet and the outlet and in airflow communication with the air flowpath, the inlet being positioned inward from the outlet along the radial direction to provide an airflow through the air flowpath.

2. The propulsion engine of claim 1 , wherein the electrical power source is an electric machine comprising a rotor and a stator, wherein the air flowpath is a cooling air flowpath in thermal communication with the electric machine, and wherein the fan blade is attached to the rotor of the electric machine.

3. The propulsion engine of claim 1 , wherein the fan blade of the fan defines an inner end and an outer end along the radial direction, wherein the inlet is defined at the inner end, and wherein the outlet is defined at the outer end.

4. The propulsion engine of claim 3 , wherein the electrical power source is an electric machine comprising a rotor and a stator, wherein the inner end of the fan blade is coupled to the rotor of the electric machine, and wherein the fan is configured to induce an airflow through the air flowpath.

5. The propulsion engine of claim 1 , wherein the propulsion engine comprises a cowling, wherein the casing is positioned within the cowling, and wherein the inlet of the fan blade is also positioned within the cowling.

6. The propulsion engine of claim 5 , wherein the cowling defines an opening, wherein the air flowpath extends from a first end through the casing to a second end, wherein the first end is in airflow communication with the opening of the cowling, and wherein the second end is in airflow communication with the inlet of the fan blade.

7. The propulsion engine of claim 6 , wherein the opening of the cowling is positioned aft of the fan blade of the fan.

8. The propulsion engine of claim 1 , wherein the electrical power source is an electric machine comprising a rotor and a stator, wherein the air flowpath is a cooling air flowpath of the propulsion engine defined at least in part by the electric machine and is in thermal communication with the stator of the electric machine.

9. The propulsion engine of claim 1 , wherein the propulsion engine is an electric fan, and wherein the electrical power source is an electric motor.

10. The propulsion engine of claim 1 , wherein the electrical power source is an electric machine, wherein the propulsion engine is a gas turbine engine comprising a fan section and a turbomachine, and wherein the fan section comprises the fan and the electric machine.

11. The propulsion engine of claim 1 , wherein the fan blade is a first fan blade of a plurality of fan blades of the fan, wherein each of the plurality of fan blades of the fan defines a respective inlet, a respective outlet, and a respective air passage extending between the respective inlet and outlet, and wherein each of the respective air passages of the plurality of fan blades is in airflow communication with the air flowpath.

12. An aeronautical vehicle comprising:

a fuselage;

a wing coupled to and extending from the fuselage; and

a propulsion system including one or more propulsion engines coupled to the fuselage, the wing, or both, each of the one or more propulsion engines defining a cooling air flowpath and comprising

an electrical power source; and

a fan comprising a fan blade rotatable by the respective electrical power source and extending generally along the radial direction, the fan blade defining an inlet, an outlet, and a cooling air passage extending between the inlet and the outlet and in airflow communication with the respective cooling air flowpath, the inlet being positioned inward from the outlet along the radial direction to provide a cooling airflow through the cooling air flowpath, wherein at least a portion of a rotor is positioned along the fan blade outward from the outlet along the radial direction.

13. The aeronautical vehicle of claim 12 , wherein the one or more propulsion engines comprises at least two propulsion engines.

14. The aeronautical vehicle of claim 12 , wherein the fan blade of the fan of each propulsion engine defines an inner end and an outer end along the radial direction, wherein the inlet is defined at the inner end, and wherein the outlet is defined at the outer end.

15. The aeronautical vehicle of claim 12 , wherein the fan blade of the fan of each propulsion engine defines an inner end and an outer end along the radial direction, wherein the inlet is defined at the inner end, wherein the outlet is defined at the outer end, wherein the outer end of the fan blade is coupled to the electrical power source of the respective propulsion engine, and wherein the fan of the respective propulsion engine is configured to provide the cooling airflow to the cooling air flowpath of the respective propulsion engine.

16. An aeronautical vehicle comprising:

a fuselage;

a wing coupled to and extending from the fuselage; and

a propulsion system including one or more propulsion engines coupled to the fuselage, the wing, or both, each of the one or more propulsion engines defining a cooling air flowpath and comprising:

an electrical power source; and a fan comprising a fan blade rotatable by the respective electrical power source and extending generally along the radial direction, the fan blade further defining an inner end and an outer end along the radial direction, wherein an inlet is defined at the inner end, wherein an outlet is defined at the outer end, wherein the outer end of the fan blade is coupled to the electrical power source of the respective propulsion engine, and wherein the fan of the respective propulsion engine is configured to provide the cooling airflow to the cooling air flowpath of the respective propulsion engine.