Hybrid electric hydrogen engine for aircraft

1. An aircraft engine system, comprising:

a core assembly comprising a compressor section, a combustor section, and a turbine section arranged along a shaft, with a core flow path through the core assembly such that exhaust from the combustor section passes through the turbine section and exits through a nozzle;

a fuel cell configured to generate electrical power;

a cryogenic fuel source configured to supply a fuel through a fuel supply line to each of the combustor section for combustion and the fuel cell for reaction to generate the electrical power;

a battery electrically connected to the fuel cell and configured to store electrical power; and

a system controller configured to selectively direct the fuel from the cryogenic fuel source to each of the combustor section and the fuel cell, wherein the system controller is configured to:

determine a state of electrical power demand associated with at least one of the aircraft engine system or an aircraft associated with the aircraft engine system relative to a threshold power requirement;

determine a current power capacity of the battery;

determine if an amount of fuel in the fuel supply line is in excess of that necessary for operation of the core assembly; based on a determination that excess fuel is present, the system controller is configured to direct at least a portion of the excess fuel from the fuel supply line to the fuel cell to generate the electrical power;

based on a determination that the state of the electrical power demand is above the threshold power requirement, direct at least a portion of the generated electrical power to the respective aircraft engine system or aircraft;

based on a determination that a current power capacity of the battery is below a threshold power capacity, direct at least a portion of the generated electrical power to the battery to charge the battery; and

based on a determination that the state of the electrical power demand is at or below the threshold power requirement and a determination that the current power capacity of the battery is at or above the threshold power capacity, vent the excess fuel from the fuel supply line.

2. The aircraft engine system of claim 1 , further comprising at least one heat exchanger arranged along the fuel supply line between the cryogenic fuel source and the combustor section and configured to heat the fuel.

3. The aircraft engine system of claim 1 , further comprising at least one turbo expander arranged along the fuel supply line between the cryogenic fuel source and the combustor section and configured to expand the fuel.

4. The aircraft engine system of claim 1 , further comprising at least one pump arranged along the fuel supply line between the cryogenic fuel source and the combustor section and configured to increase a pressure of the fuel.

5. The aircraft engine system of claim 1 , further comprising at least one flow controller arranged along the fuel supply line, wherein the system controller is further configured to control the flow controller and prevent back pressure or back flow of fuel in the fuel supply line from reentering the cryogenic fuel source.

6. The aircraft engine system of claim 1 , wherein

the venting of the excess fuel from the fuel supply line comprises venting the excess fuel out of the fuel supply line and into a storage tank for temporary storage.

7. The aircraft engine system of claim 1 , wherein the fuel is hydrogen.

8. A method of operating an aircraft engine system, the aircraft engine system comprising a core assembly, a fuel cell, a battery, and a system controller, the method comprising:

selectively supplying a fuel from a cryogenic fuel source through a fuel supply line to a combustor of the core assembly and to the fuel cell;

determining a state of electrical power demand associated with at least one of the core assembly or an aircraft associated with the core assembly relative to a threshold power requirement;

determining a current power capacity of the battery;

determining if an amount of fuel in the fuel supply line is in excess of that necessary for operation of the core assembly;

based on a determination that excess fuel is present, directing at least a portion of the excess fuel from the fuel supply line to the fuel cell to generate electrical power;

based on a determination that the state of the electrical power demand is above the threshold power requirement, directing at least a portion of the generated electrical power to the respective core assembly or aircraft;

based on a determination that a current power capacity of the battery is below a threshold power capacity, direct at least a portion of the generated electrical power to the battery to charge the battery; and

based on a determination that the state of the electrical power demand is at or below the threshold power requirement and a determination that the current power capacity of the battery is at or above the threshold power capacity, venting the excess fuel from the fuel supply line.

9. The method of claim 8 , further comprising passing the fuel through at least one heat exchanger arranged along the fuel supply line between the cryogenic fuel source and the combustor to heat the fuel.

10. The method of claim 8 , further comprising passing the fuel through at least one turbo expander arranged along the fuel supply line between the cryogenic fuel source and the combustor to expand the fuel.

11. The method of claim 8 , further comprising passing the fuel through at least one pump arranged along the fuel supply line between the cryogenic fuel source and the combustor to increase a pressure of the fuel.

12. The method of claim 8 , further comprising controlling a flow controller arranged along the fuel supply line to prevent back pressure or back flow of the fuel in the fuel supply line from reentering the cryogenic fuel source.

13. The method of claim 8 ,

wherein the venting of the excess fuel from the fuel supply line comprises venting of the excess fuel out of the fuel supply line and into a storage tank for temporary storage.

14. The method of claim 8 , wherein the fuel is hydrogen.