Abstract: A rotor blade of a turbomachine, having a blade root, a blade airfoil which has a flow leading edge, a flow trailing edge, and flow-guiding surfaces extending between the flow leading edge and the flow trailing edge. The blade root and a radially inner section of the blade airfoil are made of a steel material, and a radially outer section of the blade airfoil is made of a more lightweight material.

Abstract: A rotor blade of a turbomachine, having a blade root, a blade airfoil which has a flow leading edge, a flow trailing edge, and flow-guiding surfaces extending between the flow leading edge and the flow trailing edge. The blade root and a radially inner section of the blade airfoil are made of a steel material, and a radially outer section of the blade airfoil is made of a more lightweight material.

Abstract: A fluid flow machine, in particular turbocompressor, with a housing, having a rotor mounted in the housing, and with a dry gas seal for sealing the rotor relative to the housing. The housing at least one recess or bore for a gaseous medium is introduced, via which the gaseous medium for temperature-controlling the dry gas seal can be conducted in the direction of the same. The gaseous medium can be directly conducted into a gas space formed between the housing and the dry gas seal via the or each recess or bore. Additionally or alternatively, the or each recess or bore receives a guide tube for the gaseous medium.

Abstract: In a radial compressor stage for a radial compressor having a rotor side, the radial compressor stage includes a stator; and an impeller configured to rotate relative to the stator. The impeller has multiple impeller blades on the rotor side. Each of the multiple impeller blades has: a flow inlet edge, a flow outlet edge, a suction side extending between the flow inlet edge and the flow outlet edge, a pressure side, and an outer surface facing the stator. At least one groove is arranged in the outer surface of at least one of the multiple impeller blades, the at least one groove being bounded by a longitudinal web both on the suction side and on the pressure side. Each of the longitudinal webs forms a sealing tip of the respective impeller blade towards the stator.

Abstract: A radial compressor stage includes: an impeller, rotatable relative to a stator, the impeller having multiple impeller blades on a rotor side; a diffuser positioned in a flow direction downstream of the impeller, the diffuser having multiple guide blades on the stator side; an impeller side gap formed between the impeller and the stator; and an intermediate flow channel extending between the impeller and the diffuser. A gap is formed between an outer edge of a downstream back side of the impeller and an opposite inner edge of the stator, the gap being sealed via a seal such that the seal seals the impeller side gap from the intermediate flow channel.

Abstract: A radial compressor stage includes an impeller with multiple impeller blades on the rotor side and a diffuser with multiple guide blades on the stator side positioned downstream of the impeller. Between the impeller and the stator an impeller side gap is formed. Flow inlet edges of the guide blades on the stator side lie on a first circle contour such that the flow inlet edges of all guide blades on the stator side have an identical spacing to the flow inlet edges of the respective adjacent guide blades. Flow outlet edges of the guide blades on the stator side lie on a second circle contour such that in at least one first circumferential position the flow outlet edge of the respective guide blade on the stator side has a spacing to the flow outlet edge of at least one adjacent guide blade other than in second circumferential positions.

Abstract: A fluid flow machine, in particular turbocompressor, with a housing, having a rotor mounted in the housing, and with a dry gas seal for sealing the rotor relative to the housing. The housing at least one recess or bore for a gaseous medium is introduced, via which the gaseous medium for temperature-controlling the dry gas seal can be conducted in the direction of the same. The gaseous medium can be directly conducted into a gas space formed between the housing and the dry gas seal via the or each recess or bore. Additionally or alternatively, the or each recess or bore receives a guide tube for the gaseous medium.

Abstract: In a radial compressor stage for a radial compressor having a rotor side, the radial compressor stage includes a stator; and an impeller configured to rotate relative to the stator. The impeller has multiple impeller blades on the rotor side. Each of the multiple impeller blades has: a flow inlet edge, a flow outlet edge, a suction side extending between the flow inlet edge and the flow outlet edge, a pressure side, and an outer surface facing the stator. At least one groove is arranged in the outer surface of at least one of the multiple impeller blades, the at least one groove being bounded by a longitudinal web both on the suction side and on the pressure side. Each of the longitudinal webs forms a sealing tip of the respective impeller blade towards the stator.

Abstract: The disclosure relates to a radially fed axial steam turbine with a cold inlet duct, axially displaced from a hot inlet duct such that is it further away from a first blade row than the hot inlet duct. The cold inlet duct receives a cold steam from a cold inlet spiral and directs it into the hot inlet duct in such a way that a boundary layer of cold steam is formed over the rotor circumferential surface between the outlet end of the cold inlet duct and the blade and vane rows. The rotor circumferential surface is also adapted to promote and maintain the boundary layer. In this way, a maximum temperature to which the rotor is exposed can be reduced.

Abstract: A steam turbine is provided having a relief groove which is arranged in the region of the equalizing piston and extends in the circumferential direction of the rotor. The relief groove, with regard to an inlet passage, is arranged in the axial upstream direction so that it is arranged on the rotor outside a region in which the steam flow enters the bladed flow path via the inlet passage. The relief groove, with regard to the first blade row, is arranged in a region in which the greatest thermal stresses can arise in the rotor. As an option, the relief groove has a cover for reducing vortex flows, and also devices for reducing heating of the groove or devices for active cooling. The steam turbine allows an increased number of risk-free running up and running down operations of the steam turbine with minimum detriment to the turbine performance.

Abstract: An axial flow turbine is described having a casing defining a flow path for a working fluid therein, a rotor co-axial to the casing, a plurality of stages, each including a stationary row of vanes circumferentially mounted on the casing a rotating row of blades, circumferentially mounted on the rotor, with an inner face of the casing exposed to the working fluid having one or more essentially circumferential grooves of increasing depth each ending in an extraction port with a bore.

Abstract: A diffuser is described with an entry section close to the last stage of a turbine having an outer wall including several subsequent straight wall parts at an angle to each other followed by a curved wall part with the curved wall part connecting the straight wall parts to a diffuser lip or exit and having as vertical cross-section a non-circular 2nd order curve, preferably part of an elliptic curve.

Abstract: An axial turbine (1) has a plurality of expansion stages (2) each defined by stator blades (13) and rotor blades. The expansion stages (2) are followed by an exhaust diffuser (4) for collecting the flow passing through the expansion stages (2) and discharging it to the outside. The expansion stages (2) and/or the diffuser (4) have at least a non-axial symmetric portion. The stator blades (13) define different openings (17) along the circumference of the turbine.

Abstract: A steam turbine (10), especially for the high-pressure range or intermediate-pressure range, includes a rotor (11) which is rotatably mounted around an axis and concentrically enclosed at a distance by an inner casing (12), wherein between the rotor (11) and the inner casing (12) a flow passage (13) is formed, which on the inlet side is axially delimited by a balance piston (18) which is arranged on the rotor (11), and into which flow passage rotor blades (15) and stator blades (17), alternating in the direction of flow, radially project, and wherein, at the entry of the flow passage (13), an inlet scroll (14), through which steam is guided from the outside radially inwards and deflected in a deflection region (27) in the axial direction to the inlet of the flow passage (13), is formed on the inner casing (12).

Abstract: An exemplary control stage of a steam turbine is disclosed, which includes plural staging valves circumferentially distributed around the turbine for regulating steam admission flow so as to control the loading of the turbine. Nozzle chambers are connected to a downstream end of each staging valve. An arc of admission forms the downstream portion of each nozzle chamber, and control stage nozzles in the arcs of admission define the downstream end of the nozzle chamber. Each nozzle chamber has at least two arcs of admission, each with a different circumferential dimension.

Abstract: A steam turbine is provided having a relief groove which is arranged in the region of the equalizing piston and extends in the circumferential direction of the rotor. The relief groove, with regard to an inlet passage, is arranged in the axial upstream direction so that it is arranged on the rotor outside a region in which the steam flow enters the bladed flow path via the inlet passage. The relief groove, with regard to the first blade row, is arranged in a region in which the greatest thermal stresses can arise in the rotor. As an option, the relief groove has a cover for reducing vortex flows, and also devices for reducing heating of the groove or devices for active cooling. The steam turbine allows an increased number of risk-free running up and running down operations of the steam turbine with minimum detriment to the turbine performance.

Abstract: The disclosure relates to a radially fed axial steam turbine with a cold inlet duct, axially displaced from a hot inlet duct such that is it further away from a first blade row than the hot inlet duct. The cold inlet duct receives a cold steam from a cold inlet spiral and directs it into the hot inlet duct in such a way that a boundary layer of cold steam is formed over the rotor circumferential surface between the outlet end of the cold inlet duct and the blade and vane rows. The rotor circumferential surface is also adapted to promote and maintain the boundary layer. In this way, a maximum temperature to which the rotor is exposed can be reduced.

Abstract: An axial turbine (1) has a plurality of expansion stages (2) each defined by stator blades (13) and rotor blades. The expansion stages (2) are followed by an exhaust diffuser (4) for collecting the flow passing through the expansion stages (2) and discharging it to the outside. The expansion stages (2) and/or the diffuser (4) have at least a non-axial symmetric portion. The stator blades (13) define different openings (17) along the circumference of the turbine.

Abstract: A turbine stage includes a circumferentially distributed row of adjacent airfoils between which there is a flow passage. The passage has a surface, which in its unmodified form, defines a datum plane. A channel, located in the passage, extends in the direction of an airfoil pressure face from a point towards a leading edge line to a point towards a trailing edge line. The channel includes two channel walls angled relative to the datum plane. Relative to the datum plane, the channel has a low point, two high points, and a channel height, which is measured between the low point and the highest one of the high points. The channel provides a means to reduce secondary flow losses.

Abstract: A steam turbine is disclosed which includes a casing containing a plurality of expansion stages, each including stator and rotor airfoils. Downstream of the stator airfoils of one or more expansion stages, the casing includes a slot arranged to receive moisture that concentrates on an end wall of the stator airfoils and discharge it to the outside. Each end wall has a side portion facing the slot having a variable radial obstruction in a tangential direction, in order to define with the slot a passage through which the moisture may pass that is smaller or closed at the suction side and larger at the pressure side of the stator blades, to at least partially prevent the dry steam from entering the slot at the suction side of the blade.