Abstract: A device for simulating sound produced by certain equipment, for example a rotor-stator arrangement of a turbomachine, or for generation of opposing sound fields for active sound control, including active sound reduction and active sound amplification, comprises flow obstacles (2) provided in a flow duct (1) flown by a fluid at which vortices (5, 6) are shed at a certain frequency depending on the shape and size of the flow obstacles and the velocity of flow. The quantity and spatial arrangement of the flow obstacles is selected such that a periodically spatially and temporally changing pressure field for the excitation of a sound field (8) of a certain modal content is produced by the entirety of the vortices shed. This sound field reacts synchronizingly on the vortex shedding. The resonant circuit so formed, whose vortex shedding frequency is in the range of the resonant frequency of the sound field to be excited, is the sound source.
March 2, 2005
Date of Patent:
April 14, 2009
Roll-Royce Deutschland Ltd & Co KG
Marco Rose, Fredi Holste, Frank Arnold, Alastair D Moore
Abstract: The compressor blades of an aircraft engine are, in at least one natural-vibration critical area, designed such that at the blade leading edge (6), the leading edge shock wave (14) attaches to the leading edge (6), as a result of which a laminar boundary layer flow (7) on the suction side (13) quickly transitions into a turbulent boundary layer flow (9) which is kept constant and prevented from re-lamination by the further, continuous curvature of the suction side. Therefore, the transition, whose periodic movement is also suppressed, cannot communicate with a suction-side compression shock (10), preventing the compression shock from augmenting the natural vibrations of the blade occurring under certain flight conditions. The blade leading edge can, for example, be designed as an ellipse with a semi-axis ratio equal to or smaller than 1:4.
Abstract: On an aircraft engine with a shroudless rotor wheel arranged in a flow duct, the flow duct includes a shroud segment (1) formed by a ceramic rubbing coating (3) which, while having good thermal conductivity, is highly-temperature resistant, attaches firmly to the metallic substrate (2) and is abradable by the tips of the rotor wheel to form a sealing gap as narrow as possible, this rubbing coating, owing to the lack of self-insulation, being coolable from a free side of the metallic substrate and, therefore, permitting for working gas temperatures occurring in high-pressure turbines and coating thicknesses sufficient for abrasion.
July 23, 2004
Date of Patent:
January 20, 2009
Rolls-Royce Deutschland Ltd & Co KG
Dan Roth-Fagaraseanu, Thomas Wunderlich
Abstract: In an electronic control system, three-dimensional data sets (data cubes L11-L14) for different power-limiting engine parameters are stored at different engine ratings for setting a respective maximum engine power in relation to flight altitude (ALT), ambient temperature (DTAMB) and flight Mach number (MN) to separately calculate a maximum power corresponding to each parameter. For power reduction due to air bleed, corresponding separate data cubes (L21-L24) are stored. In a comparator, the respective smallest power reduction value is determined and, subsequently, the fuel supply is set according to that power reduction value. Under conforming boundary conditions, the same data cubes (L24) can be stored for different engine ratings. The system requires low storage capacity and low calculating effort.
Abstract: An air-guiding system between a compressor and a turbine of a gas turbine engine includes an air chamber (5) being delimited by the inner casing of the combustion chamber (4) and first and second seals (7, 8) towards the rotating compressor shaft cone (12). An axial thrust compensation chamber (6) is adjoined to said second seal (8) and respectively loaded with the turbine cooling air (B?, C) branched-off from the compressor air. Due to the higher pressure in said axial thrust compensation chamber with respect to said air chamber, the high axial forces are compensated. The air flowing back into said air chamber through said second seal (8) is guided and separated from components (10) and flowing-off air masses by a flow-guiding means (16) in said air chamber. This results in a high rinsing effect, a reduced vortex formation and finally, a reduced thermal stress.
Abstract: When forming metallic components, in particular three-dimensionally curved blades, which constitute a single piece with the blading of turbomachine rotor wheels, the linear oscillation of the electrode acting as a tool is superimposed by a circular oscillation, enabling the electrode to turn into the workpiece conformally with its shape. Further forming is performed by circular oscillation with circular feed in the one and/or the other direction. An embodiment of the corresponding apparatus comprises an electrode holder (9) with linear feed (Zvor) and linear oscillation (Zosz) and a workpiece holder (5) with circular oscillation (Cosz) and circular feed (Cvor).
Abstract: A turbine blade locking device axially retains a turbine blade (1) inserted in an axial, profiled slot (10) of a turbine disk (6). The turbine disk (6) is provided with a locking groove (8) passing through the slot (10) and extending radially in the plane of the turbine disk (6). A locking pin (4) is inserted in the locking groove (8) and the blade root (3) is provided at its bottom side with a notch (9) aligning with the locking groove (8). A portion of an elastic element (5) is arranged radially below the locking pin (4) to pre-load the locking pin (4) in a radially outward direction and into the notch (9).
Abstract: A turbomachine blade with a profile skeleton line extending along a meridional flow line, the blade being radially divided into at least three zones (Z0, Z1, Z2) with profile skeleton lines of each zone (Z0, Z1, Z2) provided in each zone from the respective radially inner to the radially outer boundary to satisfy the equations: ? * = ? 1 - ? P ? 1 - ? 2 S * = s P S where P is any point of the profile skeleton line, ?1 is angle of inclination at blade leading edge, ?2 is angle of inclination at blade trailing edge, ?* is dimensionless, specific angle of total curvature, S* is dimensionless; specific extension, ?P is angle of tangent at any point P of profile skeleton line to central meridional flow line, sP is extension of profile skeleton line at any point P, and S is total extension of profile skeleton line.
Abstract: A variable stator of a turbomachine with a profile skeleton line extending along a meridional flow line, with the stator being radially divided into at least three zones (Z0, Z1, Z2) and with the respective radial inner and the radial outer profile skeleton line of each zone (Z0, Z1, Z2) being designed such that it satisfies the following equations: ? * = ? 1 - ? P ? 1 - ? 2 S * = S P S where: P is any point of the profile skeleton line, ?1 is the angle of inclination at the stator leading edge, ?2 is the angle of inclination at the stator trailing edge, ?* is the dimensionless, specific angle of the total curvature, S* is the dimensionless, specific extension, ?P is the angle of the tangent at any point P of the profile skeleton line to the central meridional flow line, sP is the extension of the profile skeleton line at any point P, and S is the total extension of the profile skeleton line.
Abstract: A method for hard-material coating or heat treatment of the blade airfoils of blisks for gas turbines provides for partial heat-insulation and cooling of the other blisk parts during the respective process to prevent their properties from being changed by the high temperatures. The apparatus required for this method comprises two or more cooling plates (5 to 7) which are thermally insulated on their outer surfaces and include supporting flanges (20) which heat-conductively locate the blade platforms (3) of the blisks (1). Radially extending cooling medium channels (16) are provided in the cooling plates connected to a cooling medium source to continually apply cooling medium to the inner surfaces of the supporting flanges and the blade platforms.
Abstract: A turbomachine with at least one rotor (6), no or at least one stator (7), and a casing (1), with the rotor (6) comprising several rotor blades (8) attached to a rotating shaft, and with the stator (7) being provided with stationary stator blades (9). The casing (1) is passed by a fluid flowing through rotor (6) and stator (7), and means for the supply of fluid are provided on at least one blade (8, 9) of a blade row of the rotor (6) and/or the stator (7) on aerodynamically critical locations on trailing edge and rim-near surfaces (HRO).
Abstract: A turbomachine includes at least one rotor (6), at least one stator (7), and a casing (1), with the rotor (6) comprising several rotor blades (8) attached to a rotating shaft, and with the stator (7) being provided with stationary stator blades (9), the casing (1) being passed by a fluid flowing through the rotor (6) and stator (7). Provision is made for the removal of fluid on at least one blade (8, 9) of a blade row of the rotor (6) and/or the stator (7) on non-axially symmetrical, aerodynamically critical locations on blade tip and annulus surfaces (SRO).
Abstract: On a hydraulic shaft sealing arrangement for high-temperature applications, a heat protection ring (21) and an air chamber (22) are arranged before the annulus (8) containing the sealing medium (10) for thermal insulation, while spacers (16, 17) for the generation of a pumping action are provided in the annulus continuously supplied with fresh sealing medium (oil) to accelerate liquid transport. The hazard of coking and oil carbon deposition is thereby minimized. A split design of the annulus with an inserted annular ring also provides for an improved hydraulic shaft sealing arrangement optimized for weight, overall height, manufacture and assembly time.
Abstract: On an apparatus for electrochemical precision machining, the tool holder (1) performing the oscillatory motion is supported by bearing bushes (25, 26) made of a swelling material within a casing (2) performing the feed motion. The swelling, cooling and lubricating liquid is supplied from liquid chambers (4, 5) provided in the casing. A further liquid chamber (6) prevents electrolyte from ingressing into the bearing bushes. The linear oscillatory motion of the tool holder is generated by a rocker (33) which is arranged vertically to the tool holder, extends through the casing and is driven by the eccentric (30) of a drive motor (29) with an associated frequency converter. A measuring device (42) and a fastener (43) enable the tool holder to be locked in a defined position, this permitting the apparatus to be operated with high accuracy also in the non-oscillating mode of the electrode.
Abstract: A turbine blade locking device for axial retention of a turbine blade (1) having a blade root (3) inserted in an axially extending profiled lobe slot (5) of a turbine disk (4), wherein, a sealing fin of a blade platform (10) includes, over part of its axial length, a retaining groove (6) featuring a semicircular cross-section, a disk lobe (7) of the turbine disk (4) is provided with a semi-spherical recess (8), and a ball (2) is fitted into the recess (8) and the retaining groove (6).
Abstract: A gas turbine with several shroud segments (1) which enclose rotor blades (3) of a turbine wheel (5) as a seal, with the shroud segments (1) having at least a front and a rear attachment at the radially outward area of stator vane segments (7, 12), and with each of the stator vane segments (7, 12) being located at their radially inner area on a control ring (9, 10), wherein the stator vane segments (7, 12) are located on the control ring (9, 10) in a radially adjustable manner.
September 3, 2004
Date of Patent:
December 11, 2007
Rolls-Royce Deutschland Ltd & Co KG
Harald Schiebold, Olaf Mistareck, Thomas Wunderlich
Abstract: A turbomachine blade is repaired by making a leading edge cutback between two points (A) and (E) where point (A) lies within a range of relative blade height (h/H) of 0?(h/H)point A<0.85, and point (E) lies within a range of 0.95<(h/H)point E?1.0, with (h) being a blade height coordinate which originates at an end of the blade closer to starting point (A), and (H) being the blade height. A cutback trace is defined by (s/SAE) and (c/Cm), with (c) being a local cutback length in meridional flow direction, (Cm) being a meridional chord length, (s) being a local cutback length in radial direction, and (SAE) being a radial cutback length, where (c) gradually increases from point (A) to its maximum at 0.60<s/SAE<0.95, with (c/Cm) there being ?0.25, and then decreasing to ?0.05.
Abstract: An assembly fixture for the separable connection of a first component 1 and a second component 2, the first component 1 having an essentially cylindrical end-face recess 3, with the second component 2 having an essentially cylindrical protrusion 4 which fits into the recess 3, with the protrusion 4 of the second component 2 being conical at a side opposite the cylindrical side, with the first component 1 being provided with a conical face at a side facing the cylindrical side of the recess 3, and with a conical clamping body 5 which, together with the protrusion 4 of the second component 2, can be fitted into the recess 3 of the first component 1 and clamped against the first component 1.
Abstract: An inner shroud (6) for the stator blades (3) of the compressor of a gas turbine is a plastic component and includes certain additives, which may be concentrated in partial areas for specific functionality, and/or pre-manufactured inserts for sealing, ensuring sliding properties, wear protection and/or setting heat expansion. Such an inner shroud made of plastic material fulfills all requirements usually imposed on inner shrouds made of metal, while being simply producible and having low weight.
Abstract: A hollow fan blade for the fan of an aircraft engine includes a blade base section (2) and a blade tip section (5) which are assembled at opposing faying surfaces (6, 6?) by a joining process. Starting from the respective faying surface, cavities (7, 9) are produced in the two blade portions (2, 5) which are dimensioned in accordance with the loads occurring in the respective blade areas. The joining weld (4) is in a low-loaded area. The blade base section and the blade tip section can be constructed of solid material with formed-in cavities. The blade tip section can also be a sheet-metal structure.