Reverse flow hydrogen steam injected turbine engine

Patent metadata

Field	Value
Publication number	US-12428991-B2
Application number	US-202318311460-A
Country	US
Kind code	B2
Filing date	May 3, 2023
Priority date	May 19, 2022
Publication date	Sep 30, 2025
Grant date	Sep 30, 2025

Abstract

A propulsion system for an aircraft includes a gas generating core engine generates an exhaust gas flow that is expanded through a turbine section, a power turbine driven by the exhaust gas flow, a propulsor coupled to the power turbine, a hydrogen fuel system configured to supply hydrogen fuel to the combustor through a fuel flow path, a condenser arranged along the core flow path and configured to extract water from the exhaust gas flow, and an evaporator arranged along the core flow path receiving a portion of the water extracted by the condenser to generate a steam flow that is injected into the core flow path upstream of the turbine section.

First claim

What is claimed is:

1. A propulsion system for an aircraft comprising: a gas generating core engine including a core flow path where a core airflow is compressed in a compressor section, communicated to a combustor section, mixed with a hydrogen based fuel and ignited to generate an exhaust gas flow that is expanded through a turbine section; a power turbine located forward of the core engine, the power turbine configured to receive the exhaust gas flow produced by the core engine and drive a power turbine shaft; a gearbox spaced axially apart from the power turbine and coupled to the power turbine shaft; a propulsor configured to be driven by the gearbox; a hydrogen fuel system configured to supply hydrogen fuel to a combustor through a fuel flow path; a condenser arranged along the core flow path and configured to extract water from the exhaust gas flow; an evaporator arranged along the core flow path and configured to receive a portion of the water extracted by the condenser to generate a steam flow, wherein the steam flow is injected into the core flow path upstream of the turbine section, the evaporator is disposed within an axial space between the power turbine and the propulsor parallel to the power turbine shaft and the exhaust gas flow from the power turbine is directed radially outward through the evaporator to heat the portion of the water extracted by the condenser; an exhaust duct disposed radially outward from the evaporator and configured to direct the exhaust gas flow radially outward from the evaporator and axially aft to the condenser; and an inlet duct disposed radially outward of the exhaust duct and configured to direct a bypass flow radially inward to cool exhaust gas flow communicated through the condenser.

2. The propulsion system as recited in claim 1 , wherein the turbine section of the core engine is engine forward of the compressor section and the inlet duct communicates inlet air to the compressor section.

3. The propulsion system as recited in claim 2 , wherein the exhaust gas flow is communicated engine forward from the compressor section through the turbine section and then to the power turbine.

4. The propulsion system as recited in claim 3 , including the exhaust duct communicating exhaust flow from the power turbine radially outward through the evaporator to the condenser, wherein the exhaust duct is engine forward of the core engine.

5. The propulsion system as recited in claim 4 , wherein the condenser is in thermal communication with a cold sink.

6. The propulsion system as recited in claim 4 , including a water storage tank configured to receive water extracted from the exhaust gas flow by the condenser.

7. The propulsion system as recited in claim 1 , including an intercooling system to cool portions of the core airflow in the compressor section, wherein the intercooling system is configured inject water communicated from the condenser into the compressor section.

8. The propulsion system as recited in claim 1 , including a cooled cooling air passage communicating core flow from the compressor section to the turbine section, wherein a heat exchanger is disposed to cool the core flow with water from the condenser.

9. The propulsion system as recited in claim 1 , wherein the steam flow from the evaporator is injected into the combustor.

10. The propulsion system as recited in claim 1 , wherein the gas generating core engine includes a low pressure compressor coupled to low pressure turbine by a low shaft and a high pressure compressor coupled to a high pressure turbine by a high shaft.

11. The propulsion system as recited in claim 1 , further comprising a steam turbine configured to generate a work output from steam generated by the evaporator before injection into the core flow.

12. A propulsion system for an aircraft comprising: a gas generating core engine including a core flow path axially arranged through a compressor section, a combustor section and a turbine section, wherein the turbine section is engine forward of the compressor section; a power turbine located forward of the turbine section, the power turbine rotatable independent of the turbine section to drive a power turbine shaft, wherein the exhaust gas flow is communicated engine forward from the turbine section to the power turbine; a gearbox spaced axially forward of the power turbine and coupled to the power turbine shaft; a propulsor coupled to the gearbox and configured to be driven by the power turbine through the power turbine shaft and gearbox; a hydrogen fuel system configured to supply a hydrogen fuel to a combustor through a fuel flow path; a condenser arranged engine forward of the turbine section and configured to extract water from an exhaust gas flow; an evaporator arranged along the core flow path and configured to receive a portion of the water extracted by the condenser to generate a steam flow, wherein the steam flow is injected into the core flow path upstream of the turbine section, the evaporator is disposed within an axial space between the power turbine and the gearbox parallel to the power turbine shaft and radially outward of the power turbine; an exhaust gas duct disposed radially outward of the evaporator and configured to receive the exhaust gas flow exiting the evaporator and direct the exhaust gas flow radially outward and axially aft to the condenser; and an inlet duct disposed radially outward of the exhaust gas duct and configured to direct a bypass flow radially inward to cool the exhaust gas flow communicated through the condenser.

13. The propulsion system as recited in claim 12 , including the exhaust duct communicating exhaust flow from the power turbine radially outward through the evaporator to the condenser, wherein the exhaust duct is engine forward of the core engine.

14. The propulsion system as recited in claim 12 , including an intercooling system to cool portions of a core airflow in the compressor section, wherein the intercooling system is configured inject water communicated from the condenser into the compressor section.

15. The propulsion system as recited in claim 12 , including a cooled cooling air passage communicating core flow from the compressor section to the turbine section, wherein a heat exchanger is disposed to cool the core flow with water from the condenser.

16. The propulsion system as recited in claim 12 , wherein the steam flow from the evaporator is injected into the combustor.

Assignees

• Raytheon Tech Corp
• Rtx Corp

Inventors

• Chandler Jesse M
• Muldoon Marc J
• Sobanski Jon E
• Terwilliger Neil J
• Staubach Joseph B

Classifications

• F05D2260/211

  by intercooling, e.g. during a compression cycle · CPC title

• F05D2220/60

  making use of surplus or waste energy · CPC title

• F02K3/06

  with front fan · CPC title

• F02C3/305

  Increasing the power, speed, torque or efficiency of a gas turbine or the thrust of a turbojet engine by injecting or adding water, steam or other fluids (F01K21/04 takes precedence) · CPC title

• F05D2260/213

  by the provision of a heat exchanger within the cooling circuit · CPC title