Various embodiments of an airfoil and machines with airfoils are disclosed. The airfoils include a thicker leading airfoil portion and a thinner trailing airfoil portion. In one embodiment, the leading airfoil portion is formed by bending a body of the airfoil back toward itself. In another embodiment, the leading airfoil portion has a solid geometry and includes two elliptic surfaces. To prevent detachment of airflow, the leading airfoil portion includes at least two arc portions or surfaces that act to direct the airflow down to the trailing airfoil portion in a manner that stabilizes vortexes that may form in the region of changing thickness.

A method for creating an impeller and an impeller of a radial turbo fluid energy machine includes a wheel disc, cover disc, blades, and hub. The hub is mounted on a shaft which extends along an axis, the wheel disc extends substantially radially from the hub, and the cover disc is connected to the wheel disc by the blades such that flow channels separated from one another in the circumferential direction are defined by the blades. The impeller has a first flow passage in a substantially axial direction in the radial proximity of the hub, and the impeller has a second flow passage in a substantially radial direction radially farther away from the hub than the first flow path passage. The cover disc surface facing the wheel disc has a lower degree of roughness at least in some regions than the wheel disc surface facing the cover disc.

A guide vane ring for a turbomachine minimizes a leakage flow that passes through a recess (11) into which a guide vane disk is inserted. It has a guide vane row having a plurality of guide vanes (20), each having a vane airfoil (24) and a vane disk (21), as well as an inner ring (10) having an inner ring surface (12) facing the plurality of guide vanes. Viewed in the direction (R) of a designated primary flow streaming through the turbomachine, the vane disks (21) have a front and a rear surface region (22a, 22b). In a nominal and/or a maximum open position of the guide vanes, the front and/or the rear surface region (22a, 22b) of at least one of the vane disks has an offset (31a, 31b) from the inner ring surface (12) that is radially disposed (relative to a central axis (X) of the inner ring (10)).

An axial- or diagonal-fan has a fan wheel (34) having profiled rotor blades (32). Each blade has a suction or intake side (46), a portion located forward, with respect to the rotation direction (36), and having a leading edge (44), and a portion located rearward, with respect to the rotation direction (36), and having a trailing edge (92). Between said portions, on the intake side (46) of the respective rotor blade (32), a trip or separation edge (66) is provided, said trip edge having an S-shaped contour in a meridian cross-section.

A centrifugal compressor having at least a diffuser is disclosed. The diffuser has an annular diffuser body having circumferentially spaced apart diffuser passages defining fluid paths through the diffuser body. The diffuser also has a plurality of diffusion members mounted to the annular diffuser body. Each diffusion member has a member inlet in fluid communication with a diffuser passage and a member outlet. Each diffusion member defines an aerodynamic throat disposed between the member inlet and the member outlet. The diffuser also has a fluid injection assembly with multiple injection conduits. Each injection conduit extends between a conduit inlet configured to receive a flow of compressible fluid from a supply and a conduit outlet communicating with a corresponding diffusion member downstream of the aerodynamic throat. The compressible fluid is injected through the conduit outlet into the diffusion members.

A centrifugal compressor for a turbocharger includes an inlet-adjustment mechanism in an air inlet for the compressor, operable to move between an open position and a closed position in the air inlet. The inlet-adjustment mechanism includes a plurality of blades disposed about the air inlet and each pivotable about one end of the blade, the blades extending through a slot in the air inlet wall when the blades are in the closed position so as to form an orifice of reduced diameter relative to a nominal diameter of the inlet. Movement of the inlet-adjustment mechanism from the open position to the closed position is effective to shift the compressor's surge line to lower flow rates.

A profiled structure for an aircraft or turbomachine is elongated in a direction in which the structure has a length exposed to an airflow and includes serrations defined by successive teeth and depressions. The serrations may be transverse to a leading edge and/or a trailing edge of the profiled structure and in the direction of elongation. Along the profiled leading edge and/or profiled trailing edge, the successive teeth and depressions may extend only over a part of the length exposed to the flow. The amplitude and/or spacing of the teeth may vary monotonically except for the few teeth nearest each end of the part, with a remaining part of the length being smooth.

A return stage of a radial turbo fluid energy machine, in particular of a radial turbo compressor, having an axis of rotation, the return stage has an annular flow channel for feeding a flowing process fluid from a flow opening of a first impeller to a flow opening of a second impeller arranged downstream. In order to increase efficiency, the flow channel is defined by bounding surface areas, of which at least one certain rough area extending in the circumferential direction has a surface roughness that is increased in relation to the her areas.

The present disclosure relates to a diffuser for a radial compressor. The diffuser may comprise a diffusor duct portion formed by first and second side walls that are arranged so as to diverge at least partially from one another in a direction of flow, a blade ring having a number of blades arranged at least partially in the diffusor duct portion with each blade having a pressure side and a suction side delimited by a blade leading edge and by a blade trailing edge of the respective blade, a number of pressure equalizing openings incorporated into at least one of the first and second side walls of the diffuser duct portion in a region where the first and second side walls diverge from one another with each of the pressure equalizing openings being arranged between the pressure side of one blade and the suction side of an adjacent blade of the blade ring, and a first annular duct arranged behind the pressure equalizing openings and fluidically connected to the diffuser duct portion via at least two of the pressure equalizing openings, such that a number of regions between two adjacent blades of the blade ring in the diffuser duct portion are fluidically connectable together.

An assembly can include a compressor housing, an adjustable wall disposed within the compressor housing that defines an air inlet to an inducer portion of a compressor wheel, and an adjustment mechanism to adjust the wall and thereby adjust at least a diameter of the air inlet. Various other examples of devices, assemblies, systems, methods, etc., are also disclosed.