In accordance with at least one aspect of this disclosure, there is provided a drive shaft system. In embodiments, the drive shaft system includes a generator shaft extending along a longitudinal axis with a longitudinal bore defined through the generator shaft. A thru shaft extends through the longitudinal bore of the generator shaft. In embodiments, the thru shaft includes, a front coupler mount at a first end operative to receive torque input, and a rear coupler mount at a second end opposite the first end.

Turbine engine (80) components, such as blades (92), vanes (104, 106), ring segment 110 abradable surfaces 120, or transitions (85), have furcated engineered groove features (EGFs) (403, 404, 418, 509, 511, 512) that cut into the outer surface of the component's thermal barrier coating (TBC). In some embodiments, the EGF planform pattern defines adjoining outer hexagons (560, 640, 670, 690, 710). In some embodiments, the EGF pattern further defines within each outer hexagon (560, 640, 670, 690, 710) a planform pattern of adjoining inner polygons (570, 580, 590, 600, 610, 680, 682, 700, 702, 704, 705, 720). At least three respective groove segments (509, 511, 512) within the EGF pattern (506, 507, 508) converge at each respective outer hexagonal vertex (510, 564) or inner polygonal vertex (574, 564, 604, 614) in a multifurcated pattern, so that crack-inducing stresses are attenuated in cascading fashion, as the stress (σ.sub.A) is furcated (σ.sub.B, σ.sub.C) at each successive vertex juncture.

Discharge grate intended to be mounted inside or at the outlet of a conduit of a discharge valve of a turbine engine of an aircraft, the discharge grate comprising an upstream face intended to receive a gas flow, a downstream face parallel to the upstream face and intended to deliver the gas flow received on the upstream face, and orifices passing through the perforated plate from the upstream face to the downstream face and intended to convey the gas flow through the perforated plate. The discharge grate comprises for each orifice of the perforated plate a tubular channel, coaxial with the orifice with which it is associated, and projecting from the downstream face of the perforated plate.

Provided is a gas turbine vane and blade assembly in which lattice structures are installed between an impingement plate and an effusion plate. The gas turbine vane and blade assembly is capable of enhancing cooling efficiency in an impingement/effusion cooling technique.

In addition, the gas turbine vane and blade assembly can be manufactured using an additive manufacturing technique, and the lattice structures are capable of replacing supports that are used during an additive manufacturing process, and improving not only structural rigidity and stability but also cooling performance.

An aircraft propulsion assembly having an engine, a nacelle positioned around the engine, an annular duct delimited by the engine and the nacelle for a bypass flow of cold air, at least one bifurcation passing through the annular duct for connecting the engine and the nacelle and having a leading edge and a primary structure of a pylon housed in the bifurcation and configured to connect the engine to an aircraft wing. The propulsion assembly has at least one heat exchange device including a plate heat exchanger, having a hexagonal longitudinal section and positioned in the bifurcation. According to one configuration, the heat exchanger is a countercurrent heat exchanger.

Discharge grate intended to be mounted inside or at the outlet of a conduit of a discharge valve of a turbine engine of an aircraft, the discharge grate comprising an upstream face intended to receive a gas flow, a downstream face parallel to the upstream face and intended to deliver the gas flow received on the upstream face, and orifices passing through the perforated plate from the upstream face to the downstream face and intended to convey the gas flow through the perforated plate.

The discharge grate comprises for each orifice of the perforated plate a tubular channel, coaxial with the orifice with which it is associated, and projecting from the downstream face of the perforated plate.

An abradable insert for a gas turbine engine, the abradable insert including: a base layer; a lattice layer connected to the base layer, wherein the lattice layer comprises a series of walls that define a plurality of cells; and a sheet layer connected to the lattice layer on an opposite side on the lattice layer from the base layer, wherein the sheet layer is curved and includes a direction of concavity that points away from the base layer, wherein the lattice layer and the sheet layer are integrally formed together and are a monolithic piece of material.

In an embodiment, a blower for a heating, ventilation, and air conditioning system includes a blower wheel and a housing. The blower wheel includes backward-curved blades configured to rotate in a rotational plane. The housing forms an at least hexagonal cross- section around at least a portion of the rotational plane, where the blower wheel is positioned within the housing such that there exists a first distance and a second distance. The first distance is measured radially outward from a center of the blower wheel to a first side of the at least hexagonal cross-section. The second distance is measured radially outward from the center of the blower wheel to a second side of the at least hexagonal cross-section. The second distance forms a an acute angle with the first distance. The first distance and the second distance are unequal and less than a diameter of the blower wheel.

An abradable insert for a gas turbine engine, the abradable insert including: a base layer; a lattice layer connected to the base layer, wherein the lattice layer comprises a series of walls that define a plurality of cells; and a sheet layer connected to the lattice layer on an opposite side on the lattice layer from the base layer, wherein the sheet layer is curved and includes a direction of concavity that points away from the base layer, wherein the lattice layer and the sheet layer are integrally formed together and are a monolithic piece of material.

An aircraft propulsion system apparatus includes a first skin, a second skin, an intermediate layer between the first skin and the second skin, a first cellular core and a second cellular core. The first cellular core is connected to the first skin and the intermediate layer. The first cellular core includes a plurality of first core chambers, where a first of the first core chambers is fluidly coupled with one or more first perforations in the first skin and one or more first perforations in the intermediate layer. The second cellular core is connected to the intermediate layer and the second skin. The second cellular core includes a plurality of second core chambers and a plurality of corrugations, where a first of the second core chambers is fluidly coupled with the first of the first core chambers through the one or more first perforations in the intermediate layer.