In accordance with at least on aspect of this disclosure, there is provided a hydrogen fuel system for aircraft. The hydrogen fuel system includes a gas turbine engine and a fuel feed conduit. The fuel feed conduit is defined at least in part by, in fluid series, a liquid hydrogen tank fluidly connected to a combustor of the gas turbine engine, a liquid hydrogen pump to drive fuel to the combustor of the gas turbine engine, an evaporator, and an electric heat source in thermal communication with the evaporator to add heat into a flow of hydrogen passing through the evaporator. In embodiments, the electric energy source associated with the electric heat source to power the electric heat source.

A aircraft gas turbine engine and operation method, the engine including: a staged combustion system having pilot and main fuel injectors, and operates in a pilot-only range wherein fuel delivers to pilot fuel injectors, and a pilot-and-main operation range wherein fuel is delivered to at least the main fuel injectors. The engine further includes a fuel delivery regulator to pilot and main fuel injectors, which receives fuel from a first and second source containing fuels each with different characteristics. The staged combustion system switches between pilot-only and pilot-and-main range operation when in steady cruise mode, the mode defining a boundary between first and second engine cruise operation range. The fuel delivery regulator delivers fuel to pilot fuel injectors during at least part of the first engine cruise operation with different fuel characteristics from fuel delivered to one or both pilot and main fuel injectors the second engine cruise operation range.

A fuel conditioning and control system provides dynamic control and steady state operations of a gas turbine provided fueled by supercritical liquefied petroleum gas (LPG). The fuel conditioning and control system comprises a storage for LPG fuel; a fuel delivery sub-system connecting the storage to turbomachinery; and a control system. The gas turbine includes a gas turbine core control that provides at least one operational data of the gas turbine to the control system. The fuel delivery sub-system includes at least one sensor for sensing at least one property of the LPG fuel in the fuel delivery sub-system, where the at least one sensor providing data on the at least one property of the LPG fuel to the control system. The control system analyzes the data on the at least one property of the LPG fuel and at least one operational data of the gas turbine for dynamic control of LPG fuel to the gas turbine under dynamic and steady state conditions.

A method of operating a combustor of a turbomachine on a total fuel input that contains a concentration of hydrogen that is greater than about 80% is provided. The method includes injecting a first mixture of air and a first fuel containing a first amount of hydrogen into the primary combustion zone of the combustor to generate a first flow of combustion gases having a first temperature. The method further includes injecting, with one or more premix injectors disposed downstream of the fuel nozzles, a second mixture of air and a second fuel containing a second amount of hydrogen into the secondary combustion zone of the combustor to generate a second flow of combustion gases having a second temperature. The method further includes separately injecting a third fuel into secondary combustion zone to generate a third flow of combustion gases having a third temperature.

A chemical looping combustion (CLC) based power generation, particularly using liquid fuel, ensures substantially complete fuel combustion and provides electrical efficiency without exposing metal oxide based oxygen carrier to high temperature redox process. An integrated fuel gasification (reforming)-CLC-followed by power generation model is provided involving (i) a gasification island, (ii) CLC island, (iii) heat recovery unit, and (iv) power generation system. To improve electrical efficiency, a fraction of the gasified fuel may be directly fed, or bypass the CLC, to a combustor upstream of one or more gas turbines. This splitting approach ensures higher temperature (efficiency) in the gas turbine inlet. The inert mass ratio, air flow rate to the oxidation reactor, and pressure of the system may be tailored to affect the performance of the integrated CLC system and process.

A gas turbine engine including a compressor section, a combustor for combusting a fuel, and a turbine. Compressed air flows through a combustion liner of the combustor in a bulk airflow direction. The combustor includes a primary fuel nozzle and a secondary fuel nozzle. The secondary fuel nozzle is downstream of the primary fuel nozzle in the bulk airflow direction. The primary fuel nozzle is configured to inject a primary portion of the fuel into a primary combustion zone, and the secondary fuel nozzle is configured to inject a secondary portion of the fuel into a secondary combustion zone. The secondary combustion zone is located downstream of the primary combustion zone in the bulk airflow direction. The fuel may be one of diatomic hydrogen fuel and a hydrogen enriched fuel.

A propulsion system is provided and includes a solid hydride storage unit from which gaseous hydrogen fuel is drawn, an engine comprising a combustion chamber and a piping system to draw the gaseous hydrogen fuel from the solid hydride storage unit, the piping system being interposed between the solid hydride storage unit and the combustion chamber. The combustion chamber is receptive of the gaseous hydrogen fuel drawn from the solid hydride storage unit by the piping system and is configured to combust the gaseous hydrogen fuel to drive an operation of the engine.

A propulsion system is provided and includes a solid hydride storage unit from which gaseous hydrogen fuel is drawn, an engine comprising a combustion chamber and a piping system to draw the gaseous hydrogen fuel from the solid hydride storage unit, the piping system being interposed between the solid hydride storage unit and the combustion chamber. The combustion chamber is receptive of the gaseous hydrogen fuel drawn from the solid hydride storage unit by the piping system and is configured to combust the gaseous hydrogen fuel to drive an operation of the engine.

In one aspect of the present disclosure, there is provided a gas turbine engine. The gas turbine engine includes a primary gas path having, in fluid series communication: an air inlet, a compressor fluidly connected to the air inlet, a combustor fluidly connected to an outlet of the compressor, and a turbine section fluidly connected to an outlet of the combustor section. In embodiments, a hydrogen expansion turbine is in fluid communication to receive hydrogen from the gaseous hydrogen outlet of the heat exchanger. In certain embodiments, the gas turbine engine includes a heat exchanger having a gas conduit fluidly connected to the primary gas path, and a fluid conduit in fluid isolation from the gas conduit and in thermal communication with the gas conduit.

In one aspect of the present disclosure, there is provided a gas turbine engine. The gas turbine engine includes a primary gas path having, in fluid series communication: an air inlet, a compressor fluidly connected to the air inlet, a combustor fluidly connected to an outlet of the compressor, and a turbine section fluidly connected to an outlet of the combustor section. In embodiments, a hydrogen expansion turbine is in fluid communication to receive hydrogen from the gaseous hydrogen outlet of the heat exchanger. In certain embodiments, the gas turbine engine includes a heat exchanger having a gas conduit fluidly connected to the primary gas path, and a fluid conduit in fluid isolation from the gas conduit and in thermal communication with the gas conduit.