An impeller for a centrifugal compressor, the impeller rotatable about a central axis, has: an outer hub body including a first material and extending around the central axis, the outer hub body defining a gaspath face extending from an inlet to an outlet, the gaspath face extending radially away from the central axis from the inlet to the outlet; blades protruding from the gaspath face and circumferentially distributed around the central axis; and an inner hub body extending around the central axis, the inner hub body secured to the outer hub body, the outer hub body axially overlapping and extending around the inner hub body, the inner hub body made of a second material being more cold dwell resistant than the first material.

A process for cold working of the inner surface of a bore in a centrifugal compressor wheel along only a fractional portion of the bore length (i.e., along less than a full axial length of the bore), thereby creating a zone of compressive residual hoop stress in the metal surrounding the bore where the wheel needs the beneficial residual stress. The process purposefully avoids cold working of the bore at locations adjacent to high-stress areas and features of the wheel, where cold working in such locations could negatively impact the wheel's overall life.

A forced induction device for an internal combustion engine is provided, which includes a shaft, and a compressor wheel that is threadably mounted to the shaft, and a tool that is configured to engage one or more through bores in the compressor wheel to thread and unthread the compressor wheel onto and off of the shaft. The compressor wheel has a plurality of blades with leading edges that converge at an apex. The apex is aligned with a centerline of the shaft. The tool allows a technician to rotate the compressor wheel relative to the shaft to install or remove the compressor wheel from the shaft without applying any pressure to the blades of the compressor wheel. An associated assembly method is also provided.

An impeller includes: a disk-shaped hub centered on an axis; and a plurality of blades arranged in a circumferential direction and protruding from a surface of the hub facing one side in a direction of the axis. In a cross-sectional view including a blade height direction which is a direction away from the hub toward a tip of each blade, the blade has a recessed surface curved convexly toward a rear side in a rotational direction. In the cross-sectional view, when a distance between an imaginary line connecting a tip-side edge and a hub-side edge of the blade and a midspan of the blade along a direction perpendicular to the imaginary line is defined as a recess amount, the blade has a portion where the recess amount increases from a leading edge side to a trailing edge side.

A turbomachine housing, in particular of a radial turbomachine which transfers technical work to a process fluid or from a process fluid, includes: an opening extending along an axis, for the axial feed-through of a shaft extending along said axis; a contact surface extending along a circumferential direction with respect to the axis, for contact with a housing jacket of the turbomachine housing. A flow line provided as an inflow or outflow of the process fluid is designed as an integral part of the cover.

High cycle fatigue (HCF) in a turbine wheel of a sector-divided dual volute turbocharger, particularly a turbocharger where the tongue-to-blade gap is as small as from 1-3% of the wheel diameter, is reduced, and energy extraction is optimized, using a turbine wheel with (blade stiffness/backwall stiffness×100) between 41 and 44.

A turbocharger turbine wheel can include a hub that includes a rotational axis, a backdisk and a nose, where the rotational axis defines an axial coordinate (z) in a cylindrical coordinate system that includes a radial coordinate (r) and an azimuthal coordinate (Θ) in a direction of intended rotation about the rotational axis; and blades that extend outwardly from the hub, where each of the blades includes an inducer portion and an exducer portion, where, in the inducer portion, in a direction outwardly from the hub, each of the blades includes positive lean angles, a zero lean angle and negative lean angles and where, in the exducer portion, in a direction outwardly from the hub, each of the blades includes negative lean angles, a zero lean angle and positive lean angles.

A dual entry turbine of a compression device includes a housing having a first inlet and a second inlet, and a first outlet and a second outlet. A turbine impeller is arranged within the housing. The turbine impeller has a first gas path and a second gas path. A first flow path extends from the first inlet to the first outlet via the first gas path and a second flow path extends from the second inlet to the second outlet via the second gas path. The first flow path and the second flow path being fluidly separate from one another.

A turbine rotor includes a base and a plurality of blades. A central nose is radially inward of the blades and defines an axis of rotation. A plurality of cooling manifolds is disposed within the turbine rotor and includes impingement cooling jets extending through a rear surface of the turbine rotor. An internal cooling manifold extends radially inward of the impingement cooling jets and extends between the base and the rear surface of the turbine rotor. A central nose cooling manifold extends into the central nose and is fluidically connected to the internal cooling manifold. A base cooling manifold is fluidically connected to the central nose manifold and extends radially outward from the central nose cooling manifold. A blade cooling manifold is fluidically connected to the base cooling manifold and extends within the blade. Trailing edge jets extend from the blade cooling manifold and through the trailing edge of blades.

A process for treating a centrifugal compressor wheel includes a combination of cold expansion of at least part of the bore of the wheel to induce residual compressive stresses in a region around the bore, and surface peening at least parts of the compressor wheel such as the back disk and portions of the blades.