Abstract: An aircraft power system includes an internal combustion core engine where an inlet airflow is mixed with a fuel and ignited to generate shaft power and a primary gas flow, a boost combustor where a portion of the primary gas flow from the core engine is combined with fuel and ignited to generate a boosted gas flow, and a drive turbine that includes a drive output shaft wherein the boosted gas flow is expanded to generate shaft power.

Abstract: A control system for limiting power turbine torque (QPT) of a gas turbine engine includes a controller including a processor and memory configured to control the gas turbine engine, the controller including an engine control module that provides an effector command signal to a gas generator of the gas turbine engine; a power turbine governor module that outputs a preliminary torque request (QPT_req_pre); and a power turbine torque (QPT) optimal limiter module that outputs a maximum torque topper (QPT_max) to limit a power turbine speed overshoot of the gas turbine engine; wherein the controller outputs a minimum value between the preliminary torque request (QPT_req_pre) and the maximum torque topper (QPT_max) to the engine control module.

Abstract: A display system modifies display cycles of one or more displays to perform a system operation while avoiding visual perturbations at the one or more displays. The display system modifies, synchronizes, or both, blanking periods of the one or more displays such that blanking periods equal or exceed a blackout duration and overlap for at least the blackout duration. Then the system performs the system operation during an overlapping portion of the one or more blanking periods, where the system operation reduces availability of display data at the one or more displays.

Abstract: A turbine engine assembly includes a turbine section including at plurality of turbine stages through which the gas flow expands to generate a mechanical power output. An inter-turbine burner between at least two of the plurality of turbine stages reheats the gas flow. A condenser extracts water from the gas flow exhausted from the turbine section, and an evaporator heats the water extracted by the condenser to generate a steam flow with the steam flow communicated to the inter-turbine burner and added to the gas flow expanded through the turbine section.

Abstract: The present invention features interferon-free therapies for the treatment of HCV. Preferably, the treatment is over a shorter duration of treatment, such as no more than 12 weeks. In one aspect, the treatment comprises administering at least two direct acting antiviral agents to a subject with HCV infection, wherein the treatment lasts for 12 weeks and does not include administration of either interferon or ribavirin, and said at least two direct acting antiviral agents comprise (a) Compound 1 or a pharmaceutically acceptable salt thereof and (b) Compound 2 or a pharmaceutically acceptable salt thereof.

Abstract: Biguanide compounds of formula where R1 comprises a cubanyl-substituted alkyl and R2 comprises a substituted or unsubstituted alkyl, and their use in the treatment of cancers and viral infections are described.

Abstract: Propulsion systems for aircraft include a fan and a low pressure turbine operably coupled to a first shaft, a low pressure compressor and an intermediate pressure turbine operably coupled to a second shaft, and a high pressure compressor and a high pressure turbine operably coupled to a third shaft. A burner is arranged between the high pressure compressor and the high pressure turbine, with a main flow path defined through the propulsion system. A hydrogen fuel system is configured to supply hydrogen fuel to the burner. A condenser is arranged along the main flow path and configured to extract water from exhaust from the burner. An evaporator is arranged along the main flow path and configured to receive a portion of the water to generate steam which is injected into the main flow path upstream from the evaporator.

Abstract: An energy supply system includes a source of gas which is at a pressure that is equal to or greater than an atmospheric pressure. The source of gas is configured to deliver the gas into a combustor where it is mixed with a fuel. The combustor is also connected to receive a source of steam. The combustor is operable to provide combustion. Products of the combustion downstream of the combustor are connected to be delivered across a turbine rotor. The turbine rotor is provided with a shaft. The turbine shaft drives a generator. An evaporator downstream of the turbine receives the products of the combustion. The evaporator is operable to heat a source of water. The source of water downstream of the evaporator is the source of steam delivered into the combustor. The gas includes greater than 80% oxygen and the fuel includes hydrogen.

Abstract: A gas turbine engine includes a core engine that includes a core flow path where air is compressed in a compressor section, communicated to a combustor section, mixed with an ammonia based fuel and ignited to generate a high energy combusted gas flow that is expanded through a turbine section. The turbine section is mechanically coupled to drive the compressor section. An ammonia flow path communicates an ammonia flow to the combustor section. A cracking device is disposed in the ammonia flow path. The cracking device is configured to decompose the ammonia flow into a fuel flow containing hydrogen (H2). At least one heat exchanger is upstream of the cracking device that provides thermal communication between the ammonia flow and a working fluid flow such that the ammonia fluid flow accepts thermal energy from the working fluid flow.

Abstract: Propulsion systems for aircraft include a fan and a low pressure turbine operably coupled to a first shaft, a low pressure compressor and an intermediate pressure turbine operably coupled to a second shaft, and a high pressure compressor and a high pressure turbine operably coupled to a third shaft. A burner is arranged between the high pressure compressor and the high pressure turbine, with a main flow path defined through the propulsion system. A hydrogen fuel system is configured to supply hydrogen fuel to the burner. A condenser is arranged along the main flow path and configured to extract water from exhaust from the burner. An evaporator is arranged along the main flow path and configured to receive a portion of the water to generate steam which is injected into the main flow path upstream from the evaporator.

Abstract: A gas turbine engine includes a core engine that includes a core flow path where air is compressed in a compressor section, communicated to a combustor section, mixed with an ammonia based fuel and ignited to generate a high energy combusted gas flow that is expanded through a turbine section. The turbine section is mechanically coupled to drive the compressor section. An ammonia flow path communicates an ammonia flow to the combustor section. A cracking device is disposed in the ammonia flow path. The cracking device is configured to decompose the ammonia flow into a fuel flow containing hydrogen (H2). At least one heat exchanger is upstream of the cracking device that provides thermal communication between the ammonia flow and a working fluid flow such that the ammonia fluid flow accepts thermal energy from the working fluid flow.

Abstract: A hybrid electric propulsion system includes a gas turbine engine having at least one compressor section and at least one turbine section operably coupled to a shaft. The hybrid electric propulsion system includes an electric motor configured to augment rotational power of the shaft of the gas turbine engine. A controller is operable to determine hybrid electric propulsion system parameters based on a composite system model and sensor data, determine a prediction based on the hybrid electric propulsion system parameters and the composite system model, determine a model predictive control optimization for a plurality of hybrid electric system control effectors based on the prediction using a plurality of reduced-order partitions of the composite system model, and actuate the hybrid electric system control effectors based on the model predictive control optimization.

Abstract: A hybrid electric propulsion system includes a gas turbine engine having at least one compressor section and at least one turbine section operably coupled to a shaft. The hybrid electric propulsion system includes an electric motor configured to augment rotational power of the shaft of the gas turbine engine. A controller is operable to determine an estimate of hybrid electric propulsion system parameters based on a composite system model and sensor data, determine a model predictive control state and a prediction based on the hybrid electric propulsion system parameters and the composite system model, determine a model predictive control optimization for a plurality of hybrid electric system control effectors based on the model predictive control state and the prediction using a plurality of reduced-order partitions of the composite system model, and actuate the hybrid electric system control effectors based on the model predictive control optimization.

Abstract: A hybrid electric gas turbine engine includes a fan section having a fan, a turbine section having a turbine drivably connected to the fan through a main shaft that extends along a central longitudinal axis, a gas generating core extending along a first axis that is radially offset from the central longitudinal axis, and an electric motor drivably connected to the main shaft, wherein the electric motor is colinear with the main shaft.

Abstract: A control system for limiting a power turbine torque of a gas turbine engine is disclosed. In various embodiments, the control system includes an engine control module configured to output an effector command signal to a gas generator of the gas turbine engine; a power turbine governor module configured to output to the engine control module a power turbine torque request signal; and a power turbine torque limiter module configured to output to the power turbine governor module a power turbine speed rate signal to limit a power turbine speed overshoot of the gas turbine engine.

Abstract: A control system for limiting power turbine torque (QPT) of a gas turbine engine includes a controller including a processor and memory configured to control the gas turbine engine, the controller including an engine control module that provides an effector command signal to a gas generator of the gas turbine engine; a power turbine governor module that outputs a preliminary torque request (QPT_req_pre); and a power turbine torque (QPT) optimal limiter module that outputs a maximum torque topper (QPT_max) to limit a power turbine speed overshoot of the gas turbine engine; wherein the controller outputs a minimum value between the preliminary torque request (QPT_req_pre) and the maximum torque topper (QPT_max) to the engine control module.

Abstract: A control system for limiting a power turbine torque of a gas turbine engine is disclosed. In various embodiments, the control system includes an engine control module configured to output an effector command signal to a gas generator of the gas turbine engine; a power turbine governor module configured to output to the engine control module a power turbine torque request signal; and a power turbine torque limiter module configured to output to the power turbine governor module a power turbine speed rate signal to limit a power turbine speed overshoot of the gas turbine engine.

Abstract: A control system for limiting power turbine torque (QPT) of a gas turbine engine includes a controller including a processor and memory configured to control the gas turbine engine, the controller including an engine control module that provides an effector command signal to a gas generator of the gas turbine engine; a power turbine governor module that outputs a preliminary torque request (QPT_req_pre); and a power turbine torque (QPT) optimal limiter module that outputs a maximum torque topper (QPT_max) to limit a power turbine speed overshoot of the gas turbine engine; wherein the controller outputs a minimum value between the preliminary torque request (QPT_req_pre) and the maximum torque topper (QPT_max) to the engine control module.

Abstract: A hybrid electric gas turbine engine includes a fan section having a fan, a turbine section having a turbine drivably connected to the fan through a main shaft that extends along a central longitudinal axis, a gas generating core extending along a first axis that is radially offset from the central longitudinal axis, and an electric motor drivably connected to the main shaft, wherein the electric motor is colinear with the main shaft.

Abstract: A hybrid electric propulsion system includes a gas turbine engine having at least one compressor section and at least one turbine section operably coupled to a shaft. The hybrid electric propulsion system includes an electric motor configured to augment rotational power of the shaft of the gas turbine engine. A controller is operable to determine an estimate of hybrid electric propulsion system parameters based on a composite system model and sensor data, determine a model predictive control state and a prediction based on the hybrid electric propulsion system parameters and the composite system model, determine a model predictive control optimization for a plurality of hybrid electric system control effectors based on the model predictive control state and the prediction using a plurality of reduced-order partitions of the composite system model, and actuate the hybrid electric system control effectors based on the model predictive control optimization.