Abstract: The present disclosure generally relates to separating solid particles from an airflow in a gas turbine engine. A system for separating debris includes a first separation device in fluid communication with an inlet flow path of a compressor and a second separation device in fluid communication with an outlet flow path of the compressor and an inlet flow path of a combustor. The first separation device is adapted to remove coarse particles from the airflow. The second separation device is adapted to remove fine particles from the airflow. The course particles have a larger mean particle diameter than the fine particles.

Abstract: A system for energy conversion, the system including a closed cycle engine containing a volume of working fluid, the engine comprising a first chamber defining an expansion chamber and a second chamber defining a compression chamber each separated by a piston attached to a connection member of a piston assembly, and wherein the engine comprises a heater body in thermal communication with the first chamber, and further wherein the engine comprises a cold side heat exchanger in thermal communication with the second chamber, and wherein a third chamber is defined within the piston, wherein the third chamber is in selective flow communication with the first chamber, the second chamber, or both.

Abstract: A fuel nozzle apparatus includes: an outer body having an exterior surface and a plurality of openings in the exterior surface. An inner body is disposed inside the outer body, cooperating with the outer body to define an annular space. A main injection ring is disposed in the annular space and includes an array of fuel posts extending outward therefrom, each fuel post including a perimeter wall defining a lateral surface and a recessed floor. Each fuel post is aligned with one of the openings and separated from the opening by a perimeter gap defined between the opening and the lateral surface. A main fuel gallery extends within the main injection ring. The main injection ring includes plurality of main fuel orifices, each main fuel orifice communicating with the main fuel gallery and extending through one of the fuel posts.

Abstract: A monolithic heat exchanger body for inputting heat to a closed-cycle engine may include a plurality of heating walls and heat sink, such as a plurality of heat transfer regions. The plurality of heating walls may be configured and arranged in an array of spirals or spiral arcs relative to a longitudinal axis of an inlet plenum. Adjacent portions of the plurality of heating walls may respectively define a corresponding plurality of heating fluid pathways therebetween, for example, fluidly communicating with the inlet plenum. At least a portion of the heat sink may be disposed about at least a portion of the monolithic heat exchanger body. The heat sink may include a plurality of working-fluid bodies, for example, including a plurality of working-fluid pathways that have a heat transfer relationship with the plurality of heating fluid pathways.

Abstract: A fuel nozzle apparatus includes: an outer body having an exterior surface and a plurality of openings in the exterior surface. An inner body is disposed inside the outer body, cooperating with the outer body to define an annular space. A main injection ring is disposed in the annular space and includes an array of fuel posts extending outward therefrom, each fuel post including a perimeter wall defining a lateral surface and a recessed floor. Each fuel post is aligned with one of the openings and separated from the opening by a perimeter gap defined between the opening and the lateral surface. A main fuel gallery extends within the main injection ring. The main injection ring includes plurality of main fuel orifices, each main fuel orifice communicating with the main fuel gallery and extending through one of the fuel posts.

Abstract: Systems and methods for converting energy are provided. In one aspect, the system includes a closed cycle engine having a piston body and a piston assembly movable within the piston body. An electric machine is operatively coupled with the piston assembly and operable to generate electrical power. An electrical device is in communication with the electric machine. The system includes a control system having sensors, a controllable device, and a controller. The controller is configured to determine whether a load change on the electric machine is anticipated based at least in part on received data indicative of a load state of the electrical device; in response to whether the load change is anticipated, determine a control command for adjusting an output of at least one of the engine and the electric machine; and cause the controllable device to adjust the output based at least in part on the control command.

Abstract: The present disclosure generally relates to monolithic superstructures for supporting a rotating shaft coupled to a rotor relative to a stator. An integral superstructure supports the rotating component. The superstructure includes a bearing portion that contacts the shaft. A stator portion, is spaced a critical dimension radially outward, from the rotor. A first annular transfer portion extends axially forward from the bearing to the stator portion. A second annular transfer portion extends axially aft from the stator portion to a mounting flange. The mounting flange connects the superstructure to a frame. The superstructure maintains a critical dimension between the rotor and the stator as the temperature of the superstructure increases. The rotor may be a compressor impeller in a gas turbine engine and the stator may be an aero component that transfers air into a combustor.

Abstract: A piston apparatus may include a plurality of piston assemblies respectively having a first piston body and a first piston disposed within a first volume defined by the first piston body, a second piston body and a second piston disposed within a second volume defined by the second piston body, and a connection member coupled to the first piston and the second piston. The first and second volume may respectively include an expansion chamber and a compression chamber defined by opposite sides of the corresponding piston. The respective expansion chambers may fluidly communicate with a corresponding compression chamber of another one of the piston assemblies. The first volume of a first piston assembly may fluidly communicate with the first volume and the second volume of a second piston assembly, and the first volume of a third piston assembly may fluidly communicate with the first volume and the second volume of the second piston assembly.

Abstract: An energy conversion apparatus may include an engine assembly, such as a monolithic engine assembly, that includes a first heater body and a first engine body. The first heater body may define a first portion of a first monolithic body or at least a portion of a first monolithic body-segment. The first engine body may define a second portion of the first monolithic body or at least a portion of a second monolithic body-segment operably coupled or operably couplable to the first heater body. The engine assembly may include a second heater body and/or a second engine body. The second heater body may define a portion of a second monolithic body or a third monolithic body-segment. The second engine body may define a portion of the second monolithic body or a fourth monolithic body-segment operably coupled or operably couplable to the second heater body and/or the first engine body.

Abstract: Systems and methods for converting energy are provided. In one aspect, the system includes a closed cycle engine defining a cold side. The system also includes a bottoming-cycle loop. A pump is operable to move a working fluid along the bottoming-cycle loop. A cold side heat exchanger is positioned along the bottoming-cycle loop in a heat exchange relationship with the cold side of the closed cycle engine. A constant density heat exchanger is positioned along the bottoming-cycle loop downstream of the cold side heat exchanger and upstream of an expansion device. The constant density heat exchanger is operable to hold a volume of the working fluid flowing therethrough at constant density while increasing, via a heat source, the temperature and pressure of the working fluid. The expansion device receives the working fluid at elevated temperature and pressure and extracts thermal energy from the working fluid to produce work.

Abstract: An engine body may include a piston body comprising a piston chamber and a regenerator body comprising a regenerator conduit. An engine body may include a working-fluid heat exchanger body comprising a plurality of working-fluid pathways fluidly communicating between the piston chamber and the regenerator conduit. Additionally, or alternatively, an engine body may include a heater body comprising a plurality of heating fluid pathways and the plurality of working-fluid pathways. The heating fluid pathways may have a heat transfer relationship with the working fluid pathways. The working-fluid pathways may fluidly communicate between the piston chamber and the regenerator conduit. The engine body may include a monolithic body defined at least in part by the piston body, the regenerator body, and the working-fluid heat exchanger body, and/or defined at least in part by the piston body, the regenerator body, and the heater body.

Abstract: A constant density heat exchanger and system for energy conversion is provided. The constant density heat exchanger includes a housing extending between a first end and a second end and defining a chamber having an inlet and an outlet. A first flow control device is positioned at the inlet of the chamber and movable between an open position in which a working fluid is permitted into the chamber and a closed position in which the working fluid is prevented from entering the chamber. A second flow control device is positioned at the outlet of the chamber and movable between an open position in which the working fluid is permitted to exit the chamber and a closed position in which the working fluid is prevented from exiting the chamber. A heat exchange fluid imparts thermal energy to the volume of working fluid as the first flow control device and the second flow control device hold the volume of working fluid at constant density within the chamber.

Abstract: An engine apparatus, in which each piston assembly includes a piston attached to a connection member at a first end and a second end. Each piston of the piston assembly defines a first chamber and a second chamber separated by the piston. The first chamber and the second chamber are each defined at the first end and at the second end. Each first chamber of one piston assembly is fluidly connected to the second chamber at a different piston assembly. At least one first chamber at the first end is fluidly connected to a respective second chamber at the second end. At least one first chamber at the second end is fluidly connected to a respective second chamber at the first end.

Abstract: A turbomachine includes a compressor section, a turbine section, and a rotary component. The rotary component is attached to and rotatable with a portion of at least one of the compressor section and the turbine section. The turbomachine additionally includes a seal having a gas bearing. The gas bearing defines an inner surface along a radial direction of the turbomachine, a high pressure end, and a low pressure end. The gas bearing supports the rotary component and also prevents an airflow from the high pressure end to the low pressure end between the rotary component and the inner surface of the gas bearing.

Abstract: A method of manufacturing a green body part comprises depositing a layer of a powder on a working surface; and selectively depositing a binder solution comprising a thermoplastic binder, a fluorescent material, and a binder medium into the layer of powder in a pattern representative of a structure of a layer of the green body part. The thermoplastic binder comprises one or more polymer strands dissolved in a solvent medium having an average molecular weight from greater than or equal to 7,000 g/mol to less than or equal to 100,000 g/mol. Binder solutions comprising fluorescent material and green body parts adhered together using the same are also disclosed.

Abstract: A monolithic combustor body may provide multi-stage combustion. A combustor body may include a combustion chamber body and a plurality of heating walls that include a heat sink. The combustion chamber body may be disposed annularly about a longitudinal axis and defining a combustion chamber. The plurality of heating walls may include heat sink. The plurality of heating walls may occupy a radially or concentrically outward position relative to the combustion chamber and may define a corresponding plurality of combustion-gas pathways fluidly communicating with at least a proximal portion of the combustion chamber.

Abstract: A monolithic engine assembly may include an engine body that includes a regenerator body. The engine body and the regenerator body may respectively define at least a portion of a monolithic body, or the engine body may define at least a portion of a first monolithic body-segment and the regenerator body may define at least a portion of a second monolithic body-segment operably coupled or operably couplable to the first monolithic body-segment. The regenerator body may include a regenerator conduit, and a plurality of fin arrays adjacently disposed within the regenerator conduit and respectively supported by the regenerator conduit in spaced relation to one another. The spaced relation of the plurality of fin arrays may define a gap longitudinally separating adjacent ones of the plurality of fin arrays.

Abstract: The present disclosure generally relates to monolithic superstructures for supporting a rotating shaft coupled to a rotor relative to a stator. An integral superstructure supports the rotating component. The superstructure includes a bearing portion that contacts the shaft. A stator portion, is spaced a critical dimension radially outward, from the rotor. A first annular transfer portion extends axially forward from the bearing to the stator portion. A second annular transfer portion extends axially aft from the stator portion to a mounting flange. The mounting flange connects the superstructure to a frame. The superstructure maintains a critical dimension between the rotor and the stator as the temperature of the superstructure increases. The rotor may be a compressor impeller in a gas turbine engine and the stator may be an aero component that transfers air into a combustor.

Abstract: A method for integrally manufacturing a stator core and a housing for an electrical machine includes printing, by a three-dimensional (3D) printing process, the stator core. In addition, the method includes printing, by the 3D printing process, the housing. In particular, printing the housing occurs contemporaneously with printing the stator core. The method also includes printing, by the 3D printing process, at least one end cap and coupling the at least one end cap to the housing to enclose a cavity defined by the housing.

Abstract: Gas turbine engines, as well as outer walls and flow path assemblies of gas turbine engines, are provided. For example, an outer wall of a flow path comprises a combustor portion extending through a combustion section, and a turbine portion extending through at least a first turbine stage of a turbine section. The combustor and turbine portions are integrally formed as a single unitary structure that defines an outer boundary of the flow path. As another example, a flow path assembly comprises a combustor dome positioned a forward end of a combustor; an outer wall extending from the combustor dome through at least a first turbine stage; and an inner wall extending from the combustor dome through at least a combustion section. The combustor dome extends radially from the outer wall to the inner wall and is integrally formed with the outer and inner walls as a single unitary structure.