A micro turbine generator includes a compressor, a guide channel, an expansion chamber, and a recuperator. The expansion chamber includes an air inlet, an air outlet, and a guide vane structure. The air inlet is disposed at one end of the expansion chamber, connected with the compressor through the guide channel, and receives an air compressed by the compressor. The air outlet is disposed at the other end of the expansion chamber, connected with the recuperator, and discharges the air, allowing the air to enter the recuperator. The guide vane structure extends inward from an inner wall of the expansion chamber to allow the air to pass the guide vane structure before being discharged from the air outlet to enter the recuperator.

A gas turbine engine is provided that includes a compressor section, a turbine section, and a unitary structure. The compressor section has at least one compressor rotor stage. The turbine section has at least one turbine rotor stage. The compressor rotor stage and the turbine rotor stage are in rotational communication with each other. The unitary structure includes an outer case portion, a combustor section, a turbine nozzle, and an exhaust duct. The unitary structure configured for attachment with the turbine section and compressor section.

An assembly for use in an attritable engine includes a hub and a blade. The hub is configured to rotate about a centerline axis passing through a center of the hub and is formed with a first type of layer-by-layer additive manufacturing process. The blade is connected to and extends radially outward from the hub. The blade is formed with a second type of layer-by-layer additive manufacturing process that is different than the first layer-by-layer additive manufacturing process. The hub and the blade are integrally formed together as a single piece of material with a layer-by-layer additive manufacturing process. The blade includes a root of a first material, a platform connected to the root, an airfoil connected to and extending from the platform, and a tip connected on a distal end of the airfoil opposite from the root. The platform includes a material that is different from the first.

A multi-spool gas turbine engine comprises a low pressure (LP) spool and a high pressure (HP) spool independently rotatable about a central axis extending through an accessory gear box (AGB). The LP spool has an LP compressor, which is axially positioned between the HP compressor of the HP spool and the AGB. A tower shaft drivingly connects the HP spool to the AGB.

The present disclosure is directed to a propulsion system including a wall defining a combustion chamber inlet, a combustion chamber outlet, and a combustion chamber therebetween, a nozzle assembly disposed at the combustion chamber inlet, the nozzle assembly configured to provide a fuel/oxidizer mixture to the combustion chamber, a turbine nozzle coupled to the wall and positioned at the combustion chamber outlet, wherein the turbine nozzle defines a cooling circuit within the turbine nozzle, and a casing positioned radially adjacent to the wall, wherein a channel structure is positioned between the casing and the wall, the channel structure in fluid communication with the cooling circuit within the turbine nozzle, and wherein a flowpath is formed between the wall and the casing, the flowpath in fluid communication from the cooling circuit at the turbine nozzle to the nozzle assembly to provide a flow of oxidizer to the thereto.

A turboprop or turboshaft engine comprises a first spool including a first compressor drivingly connected to a first turbine, the first turbine further drivingly connected to a load. The engine comprising a second spool including a second compressor drivingly connected to a second turbine, the second compressor fluidly connected to the first compressor to receive compressed air therefrom. The engine further comprises a third spool including a third compressor drivingly connected to a third turbine, the third compressor fluidly connected to the second compressor to receive compressed air therefrom.

A shrouded impeller and a method of additively manufacturing the same are provided. In one example aspect, the shrouded impeller includes a hub and a shroud spaced from the hub. The shrouded impeller also includes a plurality of vanes extending between and connecting the hub and the shroud. The vanes are spaced circumferentially apart from one another. Flow passages are defined between adjacent vanes. In some implementations, the shrouded impeller is additively manufactured. During printing, one or more support structures are formed within and fill a portion of one or more of the flow passages to support the unsupported walls of the shrouded impeller, e.g., the shroud. Further, the support structures are removable from the shrouded impeller, e.g., after the shrouded impeller has been printed.

A gas turbine engine includes a first spool, a second spool, a primary combustor, and a diffuser. The first spool includes a first compressor rotationally driven by a first turbine via a first shaft. The second spool includes a second compressor driven by a second turbine via a second shaft. The first compressor, the diffuser, and the primary combustor are arranged in series to provide a compressed airflow discharged from the first compressor to the primary combustor via the diffuser, which includes walls that diverge towards the primary combustor. The second compressor is fluidly coupled to the diffuser to receive at least a portion of the compressed airflow from the diffuser. The second turbine is fluidly coupled to the diffuser to discharge an expanded airflow to the diffuser.

A reverse-core turbofan engine including a propulsor section including a fan and a fan-tip turbine configured to deliver air to a core duct, including a first portion, disposed aft of the propulsor section, and direct air aft, toward an inlet of a reverse-core gas generator, and a second portion, configured to receive air from an exit of the gas generator and direct the air forward and radially outward of the propulsor, toward the fan-tip turbine in the propulsor, thereby driving the propulsor.

The combustion device includes a combustor that combusts fuel ammonia and combustion air in a combustion chamber, wherein the combustor includes a cooling ammonia supplier that mixes the fuel ammonia into the combustion air and that supplies the fuel ammonia into the combustor.