Abstract: An axial compressor of a fluid-flow machine includes a flow path disposed between a rotor shaft and a relatively stationary housing wall. The flow path extends in an axial direction of the rotor shaft concentrically with the rotor shaft and the housing wall. A plurality of compressor stages are axially arranged in sequence along the flow path in the axial direction. Each of the compressor stages includes a rotor blades row and a guide vane row disposed after the rotor blades row in the axial direction. The flow path and the compressor stages operating therein are penetrable by a mass flow of a fluid to be compressed in a flow direction during operation of the compressor. A return is configured to return a part of the mass flow from a compressor discharge.

Abstract: The axial compressor has a two-stage guide vane cascade at the discharge-side end of the rotor. The guide vanes of the second stage of the cascade are staggered in the circumferential direction in relation to the guide vanes of the first stage in such a way that vortex streamers created by the guide vanes of the first stage cannot impinge upon the guide vanes of the second stage.

Abstract: A compressor component having an improved airfoil profile so as to eliminate previously known vibratory issues in the blade tip is disclosed. By altering the airfoil profile throughout its span, the natural frequency of the airfoil is altered so as to not coincide with a critical engine order of the compressor. Further, the present invention provides a novel airfoil profile in accordance with the coordinates of Table 1.

Abstract: A rotor for a turbomachine includes at least one moving blade row including a plurality of moving blades disposed adjacent to one another in a circumferential direction with respect to an axis of rotation. Each one of the plurality of moving blades includes a blade leaf and a blade root having an outer face, the outer face of the blade root including a blade root curved end wall contour adjacent the blade leaf in the circumferential direction. The blade root curved end wall contour has a concave curvature in an axial sectional plane of the rotor. At least one rotor shaft includes a reception slot for a respective one of the at least one moving blade row extending in the circumferential direction. Each of the plurality of moving blades is inserted into the reception slot via a respective blade root.

Abstract: A method is provided for reconditioning a turbomachine rotor, equipped with circumferentially extending grooves for accommodating blades retained in the grooves at a distance from each other by spacers. The method includes removing the blades and spacers from the grooves and hollowing out the exposed grooves, simultaneously widening the grooves to remove damage-inflicted material. At least one circumferentially extending lateral groove is introduced for accommodating a filler piece in the grooves to fill a gap between blades and hollowed-out rotor grooves. New spacers are provided which are matched to the hollowed-out grooves and have recesses which are matched to the introduced lateral grooves. Filler pieces are provided for inserting into the circumferentially extending lateral grooves and recesses of the new spacers. The blades and new spacers are inserted into the hollowed-out rotor grooves and corresponding filler pieces are inserted into the lateral grooves and matched recesses of the new spacers.

Abstract: A compressor component having an improved airfoil profile so as to eliminate previously known vibratory issues in the blade tip is disclosed. By altering the airfoil profile throughout its span, the natural frequency of the airfoil is altered so as to not coincide with a critical engine order of the compressor. Further, the present invention provides a novel airfoil profile in accordance with the coordinates of Table 1.

Abstract: The axial compressor has a two-stage guide vane cascade at the discharge-side end of the rotor. The guide vanes of the second stage of the cascade are staggered in the circumferential direction in relation to the guide vanes of the first stage in such a way that vortex streamers created by the guide vanes of the first stage cannot impinge upon the guide vanes of the second stage.

Abstract: The disclosure provides blades, and the modification thereof, for stages 18-22 of an axial compressor wherein the blades have reduced susceptibility to tip cracking. The blades and blades manufactured by the provided method have a thickened profile that results in reduced stress in response to multi frequency impulses and can have increased frequency response of the chord wise bending mode.

Abstract: A method is provided for reconditioning a turbomachine rotor, equipped with circumferentially extending grooves for accommodating blades retained in the grooves at a distance from each other by spacers. The method includes removing the blades and spacers from the grooves and hollowing out the exposed grooves, simultaneously widening the grooves to remove damage-inflicted material. At least one circumferentially extending lateral groove is introduced for accommodating a filler piece in the grooves to fill a gap between blades and hollowed-out rotor grooves. New spacers are provided which are matched to the hollowed-out grooves and have recesses which are matched to the introduced lateral grooves. Filler pieces are provided for inserting into the circumferentially extending lateral grooves and recesses of the new spacers. The blades and new spacers are inserted into the hollowed-out rotor grooves and corresponding filler pieces are inserted into the lateral grooves and matched recesses of the new spacers.

Abstract: A rotor for a turbomachine includes at least one moving blade row including a plurality of moving blades disposed adjacent to one another in a circumferential direction with respect to an axis of rotation. Each one of the plurality of moving blades includes a blade leaf and a blade root having an outer face, the outer face of the blade root including a blade root curved end wall contour adjacent the blade leaf in the circumferential direction. The blade root curved end wall contour has a concave curvature in an axial sectional plane of the rotor. At least one rotor shaft includes a reception slot for a respective one of the at least one moving blade row extending in the circumferential direction. Each of the plurality of moving blades is inserted into the reception slot via a respective blade root.

Abstract: The disclosure provides blades, and the modification thereof, for stages 18-22 of an axial compressor wherein the blades have reduced susceptibility to tip cracking. The blades and blades manufactured by the provided method have a thickened profile that results in reduced stress in response to multi frequency impulses and can have increased frequency response of the chord wise bending mode.