Abstract: An electric machine is provided herein that includes a stator assembly. The stator assembly includes a stator core having one or more lamination packages. The stator core can define an outer ring and a plurality of teeth extending from the outer ring. A cooling plate may be positioned adjacent to at least one of the one or more lamination packages. The cooling plate can define one or more channels therethrough. One or more windings can be arranged around one or more of the plurality of teeth of the stator core. A rotor can be operably coupled with the stator assembly. A cooling system can be fluidly coupled with the one or more channels of the cooling plate. The cooling system provides a cryogenic fluid through the one or more channels to cool the electric machine.

Abstract: A vehicle is provided including a structure including a skin defining an outside surface exposed to ambient cooling flow and an inside surface. The structure includes a first structural member extending from the inside surface of the skin and a second structural member extending from the inside surface of the skin; and a thermal management system including a heat exchanger assembly positioned adjacent to, and in thermal communication with, the inside surface of the skin, the heat exchanger assembly positioned at least partially between the first and second structural members of the structure.

Abstract: A gas turbine engine includes a compressor section and a turbine section together defining a core air flowpath. Additionally, a rotary component is rotatable with at least a portion of the compressor section and at least a portion of the turbine section. An electric machine is mounted coaxially with the rotary component and positioned at least partially inward of the core air flowpath along a radial direction of the gas turbine engine. A cavity wall defines at least in part a buffer cavity surrounding at least a portion of the electric machine to thermally insulate the electric machine, e.g., from the relatively high temperatures within the core air flowpath.

Abstract: Heat exchangers, heat exchanger systems, and hypersonic vehicles are provided. For example, a heat exchanger is provided that comprises a first chamber for receipt of a flow of cool fluid and a second chamber for receipt of a flow of hot fluid. The heat exchanger further comprises a buffer fluid flowpath for circulation of a buffer fluid therethrough. The buffer fluid circulates within the buffer fluid flowpath disposed between the first chamber and the second chamber to transfer heat from the hot fluid to the cool fluid. In certain embodiments, a hypersonic vehicle comprises such a heat exchanger, and the cool fluid is cryogenic or near-cryogenic fuel of the hypersonic vehicle and the hot fluid is engine bleed air from a hypersonic propulsion engine of the vehicle.

Abstract: A vehicle is provided including a structure including a skin defining an outside surface exposed to ambient cooling flow and an inside surface. The structure includes a first structural member extending from the inside surface of the skin and a second structural member extending from the inside surface of the skin; and a thermal management system including a heat exchanger assembly positioned adjacent to, and in thermal communication with, the inside surface of the skin, the heat exchanger assembly positioned at least partially between the first and second structural members of the structure.

Abstract: Flow paths and boundary layer restart features are provided. For example, a flow path comprises a flow path wall defining an inner flow path surface and an asymmetric notch defined in the flow path wall. The asymmetric notch comprises a first surface and a second surface and is asymmetric about a first line extending through an intersection of the first and second surfaces. Further, a flow boundary layer restart feature comprises a first surface extending inward with respect to a flow path surface of a flow path and a second surface extending inward with respect to the flow path surface. The second surface is asymmetric with respect to the first surface such that the first and second surfaces define an asymmetric notch. Additionally, a flow path wall may comprise an asymmetric notch that includes a flow expansion angle and a flow contraction angle that are unequal.

Abstract: A gas turbine engine includes a compressor section and a turbine section together defining a core air flowpath. Additionally, a rotary component is rotatable with at least a portion of the compressor section and at least a portion of the turbine section. An electric machine is mounted coaxially with the rotary component and positioned at least partially inward of the core air flowpath along a radial direction of the gas turbine engine. A cavity wall defines at least in part a buffer cavity surrounding at least a portion of the electric machine to thermally insulate the electric machine, e.g., from the relatively high temperatures within the core air flowpath.

Abstract: Flow paths and boundary layer restart features are provided. For example, a flow path comprises a flow path wall defining an inner flow path surface and an asymmetric notch defined in the flow path wall. The asymmetric notch comprises a first surface and a second surface and is asymmetric about a first line extending through an intersection of the first and second surfaces. Further, a flow boundary layer restart feature comprises a first surface extending inward with respect to a flow path surface of a flow path and a second surface extending inward with respect to the flow path surface. The second surface is asymmetric with respect to the first surface such that the first and second surfaces define an asymmetric notch. Additionally, a flow path wall may comprise an asymmetric notch that includes a flow expansion angle and a flow contraction angle that are unequal.

Abstract: An electric machine is provided herein that includes a stator assembly. The stator assembly includes a stator core having one or more lamination packages. The stator core can define an outer ring and a plurality of teeth extending from the outer ring. A cooling plate may be positioned adjacent to at least one of the one or more lamination packages. The cooling plate can define one or more channels therethrough. One or more windings can be arranged around one or more of the plurality of teeth of the stator core. A rotor can be operably coupled with the stator assembly. A cooling system can be fluidly coupled with the one or more channels of the cooling plate. The cooling system provides a cryogenic fluid through the one or more channels to cool the electric machine.

Abstract: A cross-flow heat exchanger for gas turbine engines which may be utilized to transfer heat from one fluid flow 46 to a second independent fluid flow wherein one of the fluid flows has a high differential inlet pressure and temperature. The heat exchanger has robust construction to inhibit mixing of the fluid flows during a single burst duct event.

Abstract: A gas turbine engine includes a compressor section and a turbine section together defining a core air flowpath. Additionally, a rotary component is rotatable with at least a portion of the compressor section and at least a portion of the turbine section. An electric machine is mounted coaxially with the rotary component and positioned at least partially inward of the core air flowpath along a radial direction of the gas turbine engine. A cavity wall defines at least in part a buffer cavity surrounding at least a portion of the electric machine to thermally insulate the electric machine, e.g., from the relatively high temperatures within the core air flowpath.

Abstract: A heat exchanger can include a cooling air conduit having at least one baffle, as well as a hot air conduit having at least two passes through the cooling air conduit. The heat exchanger can further include at least one perforation extending into the least one baffle. The perforation can have a passage connecting an inlet to an outlet.

Abstract: A curvilinear plate for a heat exchanger is provided. The curvilinear plate can include an inner plate defining a plurality of first grooves and an outer plate defining a plurality of second grooves. The outer plate is attached to the inner plate with the plurality of first grooves and the plurality of second grooves substantially aligned to define a plurality of channels therebetween. Each channel extends from a first opening on a first portion of a first end of the curvilinear plate to a second opening on a second portion of the first end. A method is also generally provided for forming a curvilinear plate.

Abstract: Heat exchangers, heat exchanger systems, and hypersonic vehicles are provided. For example, a heat exchanger is provided that comprises a first chamber for receipt of a flow of cool fluid and a second chamber for receipt of a flow of hot fluid. The heat exchanger further comprises a buffer fluid flowpath for circulation of a buffer fluid therethrough. The buffer fluid circulates within the buffer fluid flowpath disposed between the first chamber and the second chamber to transfer heat from the hot fluid to the cool fluid. In certain embodiments, a hypersonic vehicle comprises such a heat exchanger, and the cool fluid is cryogenic or near-cryogenic fuel of the hypersonic vehicle and the hot fluid is engine bleed air from a hypersonic propulsion engine of the vehicle.

Abstract: Flow paths and boundary layer restart features are provided. For example, a flow path comprises a flow path wall defining an inner flow path surface and an asymmetric notch defined in the flow path wall. The asymmetric notch comprises a first surface and a second surface and is asymmetric about a first line extending through an intersection of the first and second surfaces. Further, a flow boundary layer restart feature comprises a first surface extending inward with respect to a flow path surface of a flow path and a second surface extending inward with respect to the flow path surface. The second surface is asymmetric with respect to the first surface such that the first and second surfaces define an asymmetric notch. Additionally, a flow path wall may comprise an asymmetric notch that includes a flow expansion angle and a flow contraction angle that are unequal.

Abstract: A vehicle is provided including a structure including a skin defining an outside surface exposed to ambient cooling flow and an inside surface. The structure includes a first structural member extending from the inside surface of the skin and a second structural member extending from the inside surface of the skin; and a thermal management system including a heat exchanger assembly positioned adjacent to, and in thermal communication with, the inside surface of the skin, the heat exchanger assembly positioned at least partially between the first and second structural members of the structure.

Abstract: A heat exchanger is provided having an integrally and seamlessly formed return manifold connecting multiple supply tubes and return tubes. The heat exchanger may also include a return manifold having one or more structures providing a flow restriction within or proximate the return manifold.

Abstract: A cross-flow heat exchanger for gas turbine engines which may be utilized to transfer heat from one fluid flow 46 to a second independent fluid flow wherein one of the fluid flows has a high differential inlet pressure and temperature. The heat exchanger has robust construction to inhibit mixing of the fluid flows during a single burst duct event.

Abstract: A gas turbine engine includes a compressor section and a turbine section together defining a core air flowpath. The rotary component is rotatable with the compressor section and the turbine section. The gas turbine engine additionally includes an electric machine rotatable with the rotary component and positioned coaxially with the rotary component at least partially inward of the core air flowpath. The electric machine is flexibly mounted to a static frame member, or flexibly coupled to the rotary component, or both, such that the electric machine is mechanically isolated or insulated from various internal and external forces on the gas turbine engine.

Abstract: A heat exchanger can include a cooling air conduit having at least one baffle, as well as a hot air conduit having at least two passes through the cooling air conduit. The heat exchanger can further include at least one perforation extending into the least one baffle. The perforation can have a passage connecting an inlet to an outlet.