Abstract: A compressor for an aircraft engine. A rotor includes blades rotatable about an axis. Blade tips extend between leading and trailing edges. A shroud surrounds the rotor, with an inner surface surrounding the tips. Grooves are defined in the shroud inner surface adjacent the tips. The grooves extend circumferentially about the shroud and radially from inlet openings to closed end surfaces. Groove sidewalls extend circumferentially about the axis. The grooves are axially spaced-apart, the most upstream inlet opening having an upstream end disposed upstream of the leading edges of the blades. The grooves have a swept angle from the inner surface, with a center of the inlet openings is axially offset of a center of the closed-end surfaces. The grooves span an overall axial distance corresponding to 30% or more of the blades’ chord length. The grooves have circumferential interruptions defined by baffles, and extend non-continuously around a shroud circumference.

Abstract: A diffuser for a compressor of a gas turbine engine is disclosed. The diffuser has a plurality of diffuser pipes circumferentially distributed about an axis of the compressor, each of the plurality of diffuser pipes extending from an inlet to an outlet and having a bend section between the inlet and the outlet, a low pressure side and an opposite high pressure side. A recirculation conduit defines a recirculation path from a first flow region to a second flow region in one or more of the plurality of the diffuser pipes, the first flow region having a greater static pressure than that of the second region, the recirculation conduit having a conduit inlet and a conduit outlet, at least the conduit outlet located within the low pressure side of one of the plurality of the diffuser pipes.

Abstract: An impeller having a hub, blades extending from the hub along respective spans from roots to tips, the blades extending along respective chords from leading edges to trailing edges, the leading edge of at least one of the blades having a cutback section defining a sweep at the root, the cutback section extending in a spanwise direction from the hub to a location at least about 5% of the span from the hub of the at least one of the blades, and the cutback section extending in a chordwise direction along at least about 5% of the chord of the at least one of the blades

Abstract: The centrifugal impeller can have a hub and a plurality of blades, each of the blades having a span extending from the hub to a tip edge, camber lines extending from an inlet edge to an outlet edge between two opposite faces, including a tip camber line extending along the tip edge and a 50% span camber line extending at 50% of the span, a thickness extending between opposite faces of each blade, the tip edge having, at a location corresponding to 5% of the tip camber line, less than 15% of the maximum thickness, each of the blades having, along the 50% span camber line, a thickness reaching at least 58% of the maximum thickness and then reducing by at least 5% of the maximum thickness within 10% of the length of the 50% span camber line.

Abstract: An impeller for a centrifugal compressor, the impeller comprising: a hub defining a rotation axis about which the impeller is rotatable; and a vane extending from the hub, the vane having a leading edge, a trailing edge, and a chord defined therebetween, a pressure side of the vane and a suction side of the vane opposite the pressure side, a vane thickness defined transversely between the pressure side and the suction side, the vane thickness reducing over at least a downstream 40% of the chord, the vane thickness having a trailing edge thickness value at the trailing edge of between 40% and 80% of a maximum thickness value of the vane thickness.

Abstract: A diffuser pipe has a tubular body defining a pipe center axis extending therethrough. The tubular body includes a first portion extending in a generally radial direction from an inlet of the tubular body, a second portion extending in a generally axial direction and terminating at a pipe outlet, and a bend portion fluidly linking the first portion and the second portion. The tubular body has a length defined between the inlet and the pipe outlet. The tubular body has cross-sectional profiles defined in a plane normal to the pipe center axis. An area of the cross-sectional profile at the pipe outlet is at least 20% greater than an area of the cross-sectional profile at a point upstream from the pipe outlet a distance corresponding to 10% of the length of the tubular body.

Abstract: The gas turbine engine described includes a first centrifugal compressor, a second centrifugal compressor, and intercompressor pipes extending therebetween. The intercompressor pipes fluidly interconnect an exit of a first impeller of the first centrifugal compressor and an inlet of a second impeller of the second centrifugal compressor. The intercompressor pipes have heat transfer structures on outer surfaces thereof to increase convective heat transfer.

Abstract: A compressor diffuser for a gas turbine engine is described which includes diffuser pipes having a tubular body defining a pipe center axis extending therethrough. The tubular body includes a first portion extending in a generally radial direction, a second portion extending in a generally axial direction and terminating at a pipe outlet, and a bend portion fluidly linking the first portion and the second portion. A first curved side wall of the tubular body along the second portion is shorter than a second curved side wall of the tubular body along the second portion. The second portion of the tubular body has a cross-sectional profile defined in a plane normal to the pipe center axis. The first curved side wall of the cross-sectional profile has a smaller radius than a radius of the second curved side wall of the cross-sectional profile.

Abstract: A gas turbine engine for an aircraft having a centrifugal compressor including an impeller with impeller blades extending from a hub, the impeller mounted for rotation about a central longitudinal axis within an outer shroud. A main flow passage wall is located on a shroud side near the impeller exit, the main flow passage wall separating a cavity disposed on the shroud side from the main flow passage. One or more apertures are defined through the main flow passage wall and extending along a respective aperture axis between the cavity and the main flow passage. The apertures have a main flow passage side opening located radially outward from the impeller exit. The aperture axis is disposed at a radial angle relative to the central longitudinal axis.

Abstract: According to some embodiments, a system, method and non-transitory computer-readable medium are provided comprising a Hypothesis Generation Engine (HGE) to receive one or more property target values for a material; a memory for storing program instructions; an HGE processor, coupled to the memory, and in communication with the HGE, and operative to execute program instructions to: receive the one or more property target values for the material; analyze the one or more property target values as compared to one or more known values in a knowledge base; generate, based on the analysis, an initial set of hypothetical structures, wherein each hypothetical structure includes at least one property target value; execute a likelihood model for each candidate material to generate a likelihood probability for each hypothetical structure, wherein the likelihood probability is a measure of the likelihood that the hypothetical structure will have the target property value; convert each hypothetical structure into a natural

Abstract: An inter-compressor case for a gas turbine engine is disclosed. The inter-compressor case comprises: an outer casing and an inner casing radially spaced apart relative to a longitudinal axis; a gas path extending from a plurality of radial inlets arranged in a circumferentially spaced apart array around the outer casing to an annular outlet defined by an axially extending downstream portion of the outer casing and an axially extending downstream portion of the inner casing; a plurality of struts having a gas path surface extending across the gas path between the outer casing and the inner casing; and a plurality of flow separators extending from the adjacent radial inlets. The flow separators have trailing edges disposed upstream of the annular outlet and include a plurality of full length flow separators and a plurality of truncated flow separators.

Abstract: A compressor diffuser for a gas turbine engine includes a plurality of diffuser passages including a first portion having a radial component, a second portion having an axial component, and a curved portion fluidly connecting the first portion and the second portion. The diffuser passages having a throat located within the first portion thereof, and including a first subset of passages and a second subset of passages. The throats of the first subset of passages have a first throat area that is different than a throat area of the throats of the second subset of passages.

Abstract: The example embodiments are directed to a system for self-learning augmented reality for use with industrial operations (e.g., manufacturing, assembly, repair, cleaning, inspection, etc.) performed by a user. For example, the method may include receiving data captured of the industrial operation being performed, identifying a current state of the manual industrial operation based on the received data, determining a future state of the manual industrial operation that will be performed by the user based on the current state, and generating one or more augmented reality (AR) display components based on the future state of the manual industrial operation, and outputting the one or more AR display components to an AR device of the user for display based on a scene of the manual industrial operation. The augmented reality display components can identify a future path of the manual industrial operation for the user.

Abstract: The present invention concerns a method of reducing fouling and increasing the efficiency of microfiltration and ultrafiltration systems by adding an effective amount of a tannin-based polymer to wastewater containing high concentrations of total dissolved solids (TDS), such as produced water, prior to filtration. Additional pretreatment to separate out and remove coagulated solids before filtration is not required. Typically, the tannin polymer used in treating the process water is a modified tannin comprised of a Mannich reaction product of an amine, an aldehyde, and a tannin.

Abstract: A compound engine assembly having an engine core including at least one internal combustion engine in driving engagement with an engine shaft, a compressor having an outlet in fluid communication with an inlet of the engine core and including at least one rotor rotatable about an axis coaxial with the engine shaft, the engine shaft in driving engagement with the compressor rotor, and a turbine section having an inlet in fluid communication with an outlet of the engine core and including at least one rotor engaged on a rotatable turbine shaft, the turbine shaft configured to compound power with the engine shaft. The turbine and engine shafts are parallel to and radially offset from one another, and the turbine shaft and the axis of the compressor rotor are parallel to and radially offset from one another. A method of driving a rotatable load of an aircraft is also discussed.

Abstract: A compressor airfoil in a gas turbine engine is presented. Opposed pressure and suction sides are joined together at chordally opposite leading and trailing edges. The pressure and suction sides extend in a span direction from a root to a tip of the airfoil. A leading edge sweep angle is defined relative to a tangent to the airfoil and flow velocity vector at a point on the leading edge. A leading edge dihedral angle is defined relative to the tangent to the airfoil and a vertical at the point on the leading edge. A ratio of the leading edge sweep angle to the leading edge dihedral angle being smaller than 1. A method of forming such airfoil is also presented.

Abstract: A compressor for a gas turbine engine with variable inlet guide vanes each defining an airfoil portion twisted such that at each location of the airfoil portion along the pivot axis, an angle is defined between a respective chord extending between the leading and trailing edges and a same reference plane containing the pivot axis and extending radially with respect to the compressor. The angle, which is measured along a direction of rotation of the rotor, varies from a minimum value near the hub side wall to a maximum value near the shroud side wall. A method of reducing vortex whistle in a radial inlet of a compressor is also provided.

Abstract: A compressor shroud has a continuous slot defined in a gaspath side surface thereof for communicating through the body of the shroud. Spaced-apart structural bridges span a rear portion of the slot in the shroud to maintain structural rigidity of the shroud. The method of forming the continuous slot is also described.