Abstract: A method is disclosed for injecting water into a multistage axial compressor of a gas turbine. With low equipment cost, a significant power enhancement can be achieved, even under changing boundary conditions, by water being injected at a plurality of points along the axial compressor, and by the injected water mass flow being controlled at the individual injection points in accordance with ambient conditions and operating parameters of the gas turbine in such a way that an evened-out loading in the individual stages of the axial compressor can be created.

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 gas turbine having a compressor is controlled at least by controlling an opening of variable inlet guide vanes between a maximum opening and a minimum opening. A function indicative of the mechanical stress undergone by compressor blades downstream of the variable inlet guide vanes has an increasing line trend from the maximum opening to the minimum opening of the variable inlet guide vanes. The function has operating windows in which the function is smaller than a stress limit and at least one intermediate window between two operating windows, in the intermediate window the function being greater than the stress limit. The variable inlet guide vanes are regulated with a given velocity when moving from one operating window to another operating window passing through an intermediate window.

Abstract: The present disclosure provides an improved first stage airfoil for a compressor blade having a unique chord length (CD), stagger angle (?) and camber angle (??). The stagger angle (?) and camber angle (??) provide improved aerodynamics while the chord length (CD) provides for reduced airfoil weight.

Abstract: An axial compressor is disclosed for compressing air, such as for a gas turbine. The axial compressor can include a rotor, having a multiplicity of rotor blades, and rotor casing. The casing and rotor can form an annular gas passage. Outside the gas passage an annular and concentric bleed air chamber, can include at least one bleed air slot in functional communication with the gas passage. At least one injection device having at least one nozzle which can inject the fluid into the gas passage via the bleed air slot.

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 present disclosure provides an improved first stage airfoil for a compressor blade having a unique chord length (CD) stagger angle (?) and camber angle (??). The stagger angle (?) and camber angle (??) provide improved aerodynamics while the chord length (CD) provides for reduced airfoil weight.

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: The present disclosure provides an improved second stage airfoil for a compressor blade having a unique chord length (CD) stagger angle (?) and camber angle (??). The stagger angle (?) and camber angle (??) provide improved aerodynamics while the chord length (CD) provides for reduced airfoil weight.

Abstract: In a method for influencing, in particular damping or suppressing, mechanical vibrations occurring during operation in a turbomachine blade (10), the mechanical vibratory energy of the turbomachine blade (10) is first converted into electrical energy and the electrical energy generated is then converted into heat loss. Effective damping which can be used especially simply and in a versatile way is achieved in that the piezoelectric effect is used in order to convert mechanical vibratory energy into electrical energy.

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: An improved second stage airfoil for a compressor blade having a unique chord length (CD), a stagger angle (?), and camber angle (??). The stagger angle (?) and camber angle (??) provide improved aerodynamics while the chord length (CD) provides for reduced airfoil weight.

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: An axial compressor is disclosed for compressing air, such as for a gas turbine. The axial compressor can include a rotor, having a multiplicity of rotor blades, and rotor casing. The casing and rotor can form an annular gas passage. Outside the gas passage an annular and concentric bleed air chamber, can include at least one bleed air slot in functional communication with the gas passage. At least one injection device having at least one nozzle which can inject the fluid into the gas passage via the bleed air slot.

Abstract: A method is disclosed for injecting water into a multistage axial compressor of a gas turbine. With low equipment cost, a significant power enhancement can be achieved, even under changing boundary conditions, by water being injected at a plurality of points along the axial compressor, and by the injected water mass flow being controlled at the individual injection points in accordance with ambient conditions and operating parameters of the gas turbine in such a way that an evened-out loading in the individual stages of the axial compressor can be created.

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: In a method for influencing, in particular damping or suppressing, mechanical vibrations occurring during operation in a turbomachine blade (10), the mechanical vibratory energy of the turbomachine blade (10) is first converted into electrical energy and the electrical energy generated is then converted into heat loss. Effective damping which can be used especially simply and in a versatile way is achieved in that the piezoelectric effect is used in order to convert mechanical vibratory energy into electrical energy.

Abstract: The present disclosure provides an improved first stage airfoil for a compressor blade having a unique chord length (CD) stagger angle (?) and camber angle (??). The stagger angle (?) and camber angle (??) provide improved aerodynamics while the chord length (CD) provides for reduced airfoil weight.