JP2014507599A - Rotor arrangement for axial turbines - Google Patents

Abstract

  The present invention comprises a profiled rotor blade section comprising a drive shaft with a corresponding rotational axis and a plurality of rotor blades, wherein each rotor blade can be acted on in the axial direction, defining an axial direction and a circumferential direction. And a rotor having a blade fixing section, each blade fixing section having a first contact area and a second contact area, wherein the first contact area is a blade of a first adjacent rotor blade. The second contact region relates to a rotor arrangement that is at least partially supported by the fixed section and at least partially supported by the blade fixed section of the second adjacent rotor blade. The present invention provides that when the blade securing section is secured to the drive shaft in a form fit connection manner and / or utilizing a screw connection, and the connection between the rotor blade and the drive shaft is in the assembled position, Formed on the shaft end face of the blade fixing section located opposite the shaft end face of the drive shaft, the connection between the profile rotor blade section and the blade fixing section of each rotor blade has a constricted outer contour Yes.

Description

  The present invention relates to a rotor assembly for an axial flow turbine having a propeller-shaped rotor for a tidal power plant or a wind power plant particularly equipped with a horizontal rotating shaft, and an assembling method thereof.

  Tidal power plants with horizontally aligned drive shafts rotating on a nacelle and driven by a propeller-shaped turbine are known and correspond to the design of a horizontal rotor structure wind power plant. With regard to tidal power plants, the rotors of this type of axial turbine are implemented as units with free flow around them or are accommodated by a jacket housing with a venturi shape for flow acceleration . The rotor assembly described hereinafter may be replaced by a further axial fluid machine such as a fan.

  Large rotors are required for effective energy utilization of slow currents in water bodies, such as continuous ocean currents or tidal currents. Consistent demands are arising especially in the field of wind power generation for offshore plants. High forces and torques arise from the area of the rotor blade attachment in the hub that is fixedly connected to the drive shaft for rotation. Correspondingly, the high-load components for the rotor blade mounting are sufficient for the tidal power plant because the tidal current fluctuations due to moon phases are strongly superimposed by the influence of weather. It must be designed with a safe margin. Thus, depending on the wave, wind direction and the existing seafloor topography of the body of water for the location of the individual plant, a meteorologically influenced flow occurs, which creates a fluctuating load on the rotor.

  Furthermore, a simplified plant concept with firmly connected rotor blades is preferred for tidal power plants because of the accessibility for more difficult maintenance operations. In many cases, the device for rotating the plant around a vertical axis is further excluded, and instead a rotor with rotor blades that can have bidirectional input flow is used. This means that when the design is typically used for wind power plants, the rotor blades cannot be moved using pitch angle adjustment at the blade position in the event of overload. As a result. The entire plant cannot be rotated by the flow. Thus, high standards arise with regard to the structural stability of the rotor blade mounting for tidal power plants, resulting in heavy, large and expensive fasteners.

  Conventionally known rotor designs for tidal power plant axial turbines are directed to modular rotors, and individual rotor blades can be assembled separately to the hub. For this purpose, the hub is provided with a receptacle for the rotor blade fastening section of the rotor blade. Such blade fastening sections are generally formed in a cylinder and are provided with a transition region to a profile rotor blade section that interacts with the flow field and has a high structural stability. For this purpose, reference is made, for example, to US Pat. Cylindrical blade fastening sections typically have a diameter that is less than the chord length of the immediately adjacent profile rotor blade section and greater than the thickness of the profile in this region. Thus, there is a constriction from which the notch effect creates an event that loads the rotor blades, and this constriction must be protected by additional structural reinforcement.

  In addition, known blade fastening sections typically comprise a fastening flange at the hub end, which forms a screw connection between the blade fastening section of the rotor blade and the hub portion of the rotating unit adjacent thereto. Used for. Such a rotor blade fastening part is disclosed for example in US Pat. Corresponding fastening flanges for rotor blades of hubs in tidal power plants are derived from US Pat. No. 6,057,049, and the flange-shaped blade fastening sections formed integrally with the profile rotor blade sections are fixed to the hub part. Covered with a fastening ring. For further rotor blade attachments, reference is made to US Pat.

International Publication No. 2010/125478 Pamphlet US Pat. No. 6,305,905 British Patent Application No. 2467226 US Pat. No. 5,173,023 British Patent No. 502409

  The present invention is based on the object of identifying a rotor assembly for an axial turbine with a plurality of individually mountable rotor blades, which provides a high structural stability of the rotor blade fasteners as well as adjacent drive shafts. Identified by efficient force and torque transmission. In addition, the rotor blade design is desired to allow easy replacement of individual rotor blades. Furthermore, the rotor assembly is particularly suitable for implementing an axial turbine that can be used to operate a tidal power plant and can preferably have a bidirectional input flow. The rotor arrangement must be able to mitigate particularly asymmetric load peaks that only act on the individual rotor blades and must be simplified in both design and manufacture. Furthermore, a method for assembling such a rotor blade assembly is sought.

  The invention is realized by the features of the independent claims. The inventor has recognized that instead of fastening individual rotor blades to the hub, the load capacity of the rotor blade mount is increased by omitting the integrated hub components. According to the invention, individual hub segments are assigned to replaceable rotor blades. These hub segments form blade fastening sections that mutually support each other at least circumferentially and at least indirectly.

  Preferably, for a rotor capable of having a bi-directional input flow, not only is circumferential pressure between the blade fastening sections mediated, but rather there is additional traction and axial force components in the circumferential direction. Alleviated by the removable connection of adjacent blade fastening sections. Screw connections and / or formfitting connections are preferably considered as removable connections, and in the case of plant maintenance, the individual rotor blades can be adjusted or replaced separately. For an advantageous embodiment, the blade fastening section forms a split hub after the assembly to the drive shaft for interaction with individual adjacent blade fastening sections.

  Each rotor blade of a rotor blade assembly according to the present invention comprises a profile blade section and a blade fastening section substantially suitably coupled thereto, the blade fastening section being a corresponding blade fastening section of an adjacent rotor. Supported and / or removably connected. The profile rotor section of the rotor blade represents the portion of the rotor blade that interacts with the flow field in a usable manner. Thus, when operated by flow in water, the profile rotor blade section is the hydrodynamically active part of the rotor blade with a matched blade profile. In the case of a rotor capable of having a bi-directional input flow for tidal power plants, a symmetrical profile can be used for this purpose, for example an elliptical shape can be given for a biaxial symmetrical profile . Alternatively, a point symmetric profile with a profile ridge, ie, a curved trailing edge profile, can be used.

  Each rotor blade has the form of a one-part, particularly preferably assigned profile rotor blade section and assigned blade fastening section. The rotor blades are made of GFRP (glass fiber reinforced plastic) or CFRP (carbon fiber reinforced plastic) or steel and are used to transfer force to the blade fastening section of the adjacent rotor blade. Are preferably reinforced by embedding an anti-wear material such as a metal coupling element. With regard to a further advantageous design, the blade fastening section is manufactured as a cast part. A profile rotor blade section made from steel, CFRP, or GFRP is substantially bonded thereon.

  For an alternative embodiment, the blade stub that formed the first portion of the profile rotor blade section is substantially coupled to the blade fastening section, and the second portion of the profile rotor blade section is removably connected to the blade stub. Has been. The transition from the first part to the second part of the profile rotor blade section can be implemented as a desired break point to protect the entire plant from severe breakage in case of overload. Furthermore, there is the possibility of providing this transition region with elasticity in order to carry out the bending-rotation connection of the rotor blades.

  The blade fastening section is connected in a form-fit connection manner and / or in a manner that is screwed to the drive shaft of the rotor assembly and each individual rotor blade is fixed to the drive shaft for rotation. Yes. This connection can be made via one or more intermediate elements, at least indirectly provided with a link fixed for rotation of the rotor blade. For a rotor blade assembly implemented in accordance with the present invention, only a portion of the force and torque induced from the profile rotor blade section is transmitted to the individual connection of the rotor blade to the drive shaft. This is because a further part of the force action is mitigated by the mutual support of adjacent blade fastening sections.

  With respect to the preferred embodiment, the connection between the rotor blade and the drive shaft is made at the axial end face of the rotor blade fastening section, facing the axial end face of the drive shaft in the assembled position. Due to the input flow to the rotor blades, in particular shear loads are generated in the axial direction, resulting in a force component in the circumferential direction of the contact area of the adjacent blade fastening section. For this reason, with respect to an advantageous embodiment of the invention, each blade fastening section comprises a first contact area and a second contact area, and a third contact area as described above in contact with the drive shaft. The first contact area and the second contact area are preferably spatially divided. The first contact region and the second contact region are alternately adjacent to each other and are coupled to each other.

  The first contact area and the second contact area are fixed by individually interacting with directly adjacent rotor blades. With respect to the first embodiment, the first contact area is at least indirectly supported by the blade fastening section of the directly adjacent first rotor blade, and the second contact area is accordingly corresponding to the directly adjacent second rotor blade. Supported at least indirectly in the blade fastening section. Thus, an axial turbine rotor having axial flow from the axial direction can be implemented in downstream operation. For rotors capable of both bidirectional operation and capable of bidirectional input flow, the first contact area and the second contact area can be removed into individual adjacent blade fastening sections of adjacent rotor blades. Means for connecting to are preferably provided. These means can be implemented as a form of screw connection and / or form fit connection.

  The contact area is particularly preferably moved into the intermediate blade area with less mechanical load. Accordingly, these intermediate blade regions are formed such that the angular offset of these regions in the circumferential direction with respect to the dividing surface between adjacent rotor blades is ± 30 ° at the maximum, and preferably ± 15 ° at the maximum. The dividing plane extends in the middle between adjacent rotor faces, the rotor faces being assigned to individual rotor blades and characterized with respect to the rotational axis of the drive shaft and the transition from the profile rotor blade section to the blade fastening section. It is spread individually by additional straight lines. In the simplest case, a rotor blade with a radial beam shape is provided, i.e. the threading line of the profile rotor blade section follows a straight line in the radial direction. In this case, the rotor surface is defined by the threading line and the rotating shaft.

  However, it may also occur when the profile rotor blade section extends in a sickle shape. Thus, an embodiment is conceivable in which the profile rotor blade section extends in the rotor plane formed as being axially symmetric with respect to the axis of rotation, but the threading line does not follow a straight line. Furthermore, it is conceivable that the profile rotor blade section is curved and the profile rotor blade section leaves the rotor surface. With respect to such a profiled, applied profile rotor blade section, a characteristic point, for example a point on the chord line at half profile depth, is within the transition from the blade fastening section to the profile rotor blade section. Is selected to define the rotor face on a predetermined profile section. As a result, the straight line and the rotary shaft extending radially through this point also form the rotor surface.

  In the case of a rotor with more than two rotor blades, the intermediate blade region is preferably between 40% and 60% of the angle formed by the sections of the rotor face with the rotor faces arranged adjacent to each other Within an angular interval. For rotors where shear forces substantially higher than torsional forces are applied, the intermediate blade region is subjected to lower loads with respect to the remaining region of the blade fastening section. The connecting element for the blade fastening section of the adjacent rotor blade is preferably located in this region. These represent, for example, components that are interlocked in a form-fit manner and can be fastened together by relative movement in the axial direction of the rotor.

  According to an advantageous embodiment, an elastic intermediate layer is provided between adjacent blade fastening sections, in particular between the contact areas facing each other. Elastomer materials with high load tolerance, commonly used to implement seawater slide bearings, take into account for this purpose. These materials are generally loadable by pressure and have a high wear resistance for a hard / soft set. The predetermined relative movement of the rotor blades that occurs due to the impact load can be compensated by the elastic intermediate layer.

  For improvement, it is conceivable to mediate a removable connection between the blade fastening sections of adjacent rotor blades with additional intermediate elements. However, for known hub components, these do not form a unitary structure, but rather are implemented as separate components arranged in a spatially divided manner. Due to the improvements of the invention, these intermediate elements can be adapted to the assembly arrangement of the rotor blades for the individual positions. This makes it possible to change the hit angle of the profile rotor blade section by the use of standardized rotor blades and the corresponding selection of rotor blade geometry, in particular intermediate elements.

  Embodiments are particularly suitable with respect to the fact that the entire rotor blade fastening section of the rotor in the engaged state accommodates the central open area, which is used to accommodate the shaft portion of the drive shaft adjacent to the rotor. It is. The contour of the central open region is particularly well designed so that this region deviates from the circular contour and transmits the drive torque generated from the rotor through a correspondingly fitted shaft connection and form-fit connection. ing.

  In addition to the movement of the connecting element to the intermediate blade region subject to lower loads, the design according to the invention makes it possible to reduce the notch effect at the transition from the profile rotor blade section to the rotor blade fastening section. This is achieved because the conventional common cylindrical design of the blade fastening section for accommodation within the hub receptacle has been replaced by the assignment of hub segments to individual rotor blades. The large blade fastening section is derived from the increase in size without the split hub portion caused by the integral coupling of the rotor blades.

  In order to reduce the notch effect, there is preferably no constriction in the region of the rotor blade radial section that defines the transition region between the profile rotor blade section and the rotor blade fastening section. A transition region that results in a continuous taper of the rotor blade beyond a limited radius in the radially outward direction is particularly suitable. Alternative embodiments are also conceivable, in which the essential profile region with respect to structural stability, i.e. the profile lug, projects somewhat above the cross-sectional area of the blade fastening section on the profile rotor blade section. The profile chord in this attachment region can exceed the cross-range of the blade fastening section by more than 20% without a substantial increase in the resulting notch effect.

  Exemplary embodiments will now be described in more detail based on the description in the figures.

1 is a perspective view illustrating a first exemplary embodiment of a rotor assembly according to the present invention in a partially assembled state. FIG. FIG. 6 is a perspective view illustrating a second exemplary embodiment of a rotor assembly according to the present invention in a partially assembled state. FIG. 6 is an axial plan view showing an alternative rotor design. FIG. 4 is an enlarged view showing details of FIG. 3. FIG. 4 shows a rotor assembly according to the invention with the rotor according to FIG. 3 in an assembled state on a drive shaft. FIG. 5 is an axial plan view showing a further alternative rotor design.

  FIG. 1 shows a schematic simplified view of a rotor assembly according to the invention with a drive shaft 1 and a rotor 20 with three rotor blades 2.1, 2.2, 2.3. ing. The drive shaft 1 includes a rotating shaft 21 that defines an axial direction 22 and a circumferential direction 23. Each rotor blade 2.1, 2.2, 2.3 has a profile rotor blade section 3.1, 3.2, 3.3 and a blade fastening section 4.1, 4.2 for interacting with the flow field 4.3. The blade fastening sections 4.1, 4.2, 4.3 are connected to the drive shaft 1 in a manner that is fixed for rotation. Bore holes 17.1 to 17. on the first shaft end face 24. n is used for this purpose and screw holes 27.1 to 27. of the shaft end face 26 of the drive shaft 1 are used. corresponds to n.

  With respect to the rotor blade 2.1, the profile rotor blade section 3.1 is substantially coupled to the assigned blade fastening section 4.1 for the preferred design shown. The further rotor blades 2.2, 2.3 result in a material bond between the individual profile rotor blade sections 3.2, 3.3 and the blade fastening sections 4.2, 4.3. Designed to be The rotor blades 2.1, 2.2, 2.3 can be produced from different structural materials. In addition to cast parts, steel and fiber composites based on GFRP and CFRP are considered for this purpose. It is also conceivable to connect different materials for the implementation of the rotor blades 2.1, 2.2, 2.3.

  Each blade fastening section 4.1, 4.2, 4.3 comprises a first shaft end face 24 and a second shaft end face 25, which are formed by plate-like elements spaced from each other. The plate-like elements are connected by an end plate, which is in the first contact area 7.1, 7.2, 7.3 and in the second contact area 8.1, 8.2, 8.3. In the assembled state, it extends in the axial cross section of the drive shaft 1 and has a lightweight structure but a torsion-resistant structure, and is easily accessible for assembly work through the side opening 32 of the box structure. Has contributed.

  In the assembled state, the first contact areas 7.1, 7.2, 7.3 for the first rotor blades 2.1, 2.2, 2.3 are directly adjacent individual rotor blades 2.1, 2.2, 2.3 facing the second contact areas 8.1, 8.2, 8.3 of the blade fastening sections 4.1, 4.2, 4.3. The first contact areas 7.1, 7.2, 7.3 and the second contact areas 8.1, 8.2, 8.3 facing each other in the assembled state are the blade fastening section in the circumferential direction 23. Used for mutual support of 4.1, 4.2, 4.3.

  With respect to the input flow 28 shown in FIG. 1, the rotor 20 is downstream. As a result, the shear forces 30.1, 30.2, 30.3 generated in the profile rotor blade sections 3.1, 3.2, 3.3 are the blade fastening sections 4.1, 4.2, 4. 3 produces a force component 29.1, 29.2, which is outlined in the circumferential direction 23, which is relaxed by the mutual contact of the blade fastening sections 4.1 and 4.3. The

  FIG. 2 illustrates the improvement of the present invention with respect to a rotor assembly capable of having bi-directional input flow, alternating compressive and traction forces outlined by force components 29.3, 29.4. In order to alleviate this, fastening means are provided in the first contact areas 7.1, 7.2, 7.3 and the second contact areas 8.1, 8.2, 8.3. The dovetail-shaped fastening elements 10.1 to 10.5 are shown as examples for this purpose, and they are already assembled components of the individual rotor blades 2.1, 2.2, 2.3. The axial movement with respect to the blade allows the integral connection of the blade fastening sections 4.1, 4.2, 4.3. Bolts are used as removable connections for the additional blade fastening sections 4.1, 4.2, 4.3. The fastening element 6 is shown in FIG. 2 as an example for this purpose.

  A further embodiment is shown in FIG. This figure shows boreholes 17.1-17.17 for fastening to the drive shaft 1, whose outline is shown in FIG. 2 shows a plan view of a first shaft end face 24 of a blade fastening section 4.1, 4.2, 4.3 with n. FIG. 4 shows the second contact area 8.2 of the blade fastening section 4.2 and the first contact area 7.3 of the blade fastening section 4.3 together with the profile rotor blade sections 3.1, 3.2, 3.. 3 is shown enlarged as a section in the plane defined by the three longitudinal axes 9.1, 9.2, 9.3. The contact areas 8.2, 7.3 are removably connected by bolts 11.1, 11.2, which contain the elastic intermediate element 13 and provide pretensioning. Elastic sliding bearing materials are suitable for this purpose, such as, for example, the elastomer material Olcott®. The elastic intermediate element 13 allows a certain ease of movement of the rotor blades 2.1, 2.2, 2.3 in the case of asymmetric loads.

  Furthermore, with respect to the preferred embodiment shown, the side openings 31 are provided in the box-shaped blade fastening sections 4.2, 4.3, reducing the weight of the rotor blade mountings, and with regard to assembly the shaft Bore holes 17.1-17 used for mounting parts. It is clear from FIG. 4 that it allows access to n.

  Furthermore, FIG. 4 shows that the point of mutual support of the blade fastening sections 4.1, 4.2, 4.3 is the force introduction area at the transition to the profile rotor blade sections 3.1, 3.2, 3.3. It is shown that it is applied in the intermediate blade regions 18.1, 18.2, 18.3. For the sake of clarity, the dividing surface 32 is outlined between the second contact area 8.2 of the blade fastening section 4.1 and the first contact area 7.2 of the blade fastening section 4.2. The dividing plane divides the angle between the longitudinal axes 9.1 and 9.2 of the profile rotor blade sections 3.1, 3.2 in half, the longitudinal axis being perpendicular to the plane of the figure (axial direction) Together with the surfaces, the rotor surfaces for rotor blades 2.1, 2.2 are defined. With respect to the rest of the blade fastening sections 4.1, 4.2, 4.3 during operation of the rotor 20, those areas where weaker loads are applied are defined by an offset angle of up to ± 15 °. Are located in the intermediate blade regions 18.1, 18.2, 18.3.

  Further structural reinforcements can be found in the transition areas 19.1, 19.2 between the profile rotor blade sections 3.1, 3.2, 3.3 and the blade fastening sections 4.1, 4.2, 4.3. , Due to the advantageous design of 19.3. The advantageous embodiment according to FIG. 3 shows a non-necked outer contour, and the notch effect in the rotor blade mounting is reduced. A continuous taper radially outward from the blade fastening section to the profile rotor blade section 3.1, 3.2, 3.3 is particularly preferably provided from a specific radius.

  In the assembled state, the blade fastening sections 4.1, 4.2, 4.3 of the rotor blades 2.1, 2.2, 2.3 removably connected to one another are centrally open with respect to the advantageous embodiments. A divided hub portion 5 having a region 14 is formed. With respect to the embodiment shown in FIG. 3, the central open region 14 is triangular with respect to the sections in the rotor plane. Such a central open region 14 of the split hub portion 5 deviating from the circle is such that after all the rotor blades 2.1, 2.2, 2.3 of the rotor 20 have been assembled together, This allows the form fit connection to be pressed against the complementary shaft connection 16 of the drive shaft 1. This is shown in FIG. 5 as a plan view of the second shaft end face 25 of the rotor 20. Borehole 17.1-17. The hidden first shaft end surface 24 with n (not shown in FIG. 5) is pressed against the shaft end surface 26 of the drive shaft 1 for fastening. The rotor 20 assembled in this manner can be partly assembled for maintenance purposes, with the individual rotor blades 2.1, 2.2, 2.3 for further rotor components or drive Separately exchanged or readjusted with respect to the relative arrangement with respect to the shaft 1. For this purpose bore holes 17.1-17. It is conceivable that n allows a predetermined degree of assembly freedom by a method using a long hole. For improvement (details not shown), a fixing element removably connected to the drive shaft 1 is adjacent to the shaft connection 16 and the fixing element is in the assembled position in the blade fastening section 4.1, 4 2. Cover the second shaft end surface 25 of 4.3, and fix in the axial direction.

  With respect to the exemplary embodiment shown in FIG. 6, the intermediate elements 13.1, 13.2, 13.3 are used to implement the removable connection of the blade fastening sections 4.1, 4.2, 4.3. Is used. These show separate components that are spatially divided and used to connect the rotor blades 2.1, 2.2, 2.3. For improvement (not shown in the figure), the intermediate elements 13.1, 13.2, 13.3 can be in a form-fit connection with the shaft connection 16 of the drive shaft 1.

  In addition, implementations using intermediate elements 13.1, 13.2, 13.3 specially adapted for plants, which implement the tilted setting of the rotor blades 2.1, 2.2, 2.3 Possible forms. The resulting irregularities at the end face of the rotor 20 facing the adjacent drive shaft 1 in this case must be supported by appropriately adapted wedge elements for reliable contact. Further embodiments result from the following protection claims.

DESCRIPTION OF SYMBOLS 1 ... Drive shaft 2.1, 2.2, 2.3 ... Rotor blade 3.1, 3.2, 3.3 ... Profile rotor blade section 4.1, 4.2, 4. DESCRIPTION OF SYMBOLS 3 ... Blade fastening section 5 ... Divided hub part 6 ... Fastening element 7.1, 7.2, 7.3 ... 1st contact area 8.1, 8.2, 8.3 .... Second contact area 9.1, 9.2, 9.3 ... Longitudinal axis 10.1-10.6 ... Form fit fastening elements 11.1, 11.2 ... Bolts 12.1 12.2, 12.3 ... Elastic intermediate layer 13.1, 13.2, 13.3 ... Intermediate blade region 14 ... Central open region 16 ... Shaft connection 17.1-17 . n: Bore hole 18.1, 18.2, 18.3: Rotor blade intermediate region 19.1, 19.2, 19.3 ... Transition region 20 ... Rotor 21 ... Rotating shaft 22 ... Axial direction 23 ... Circumferential direction 24 ... First shaft end face 25 ... Second shaft end face 26 ... Shaft end face 27.1-27. n ... Screw hole 28 ... Input flow 29.1, 29.2, 29.3, 29.4 ... Force components 30.1, 30.2, 30.3 ... Shear force 31 ... Side opening 32 ... Dividing surface 33 ... Offset angle

The present invention relates to a particular rotor assemblies for an axial flow turbine with a rotor of a propeller shape for horizontal shaft tidal power plants or wind power plant equipped with.

Conventionally known rotor designs for tidal power plant axial turbines are directed to modular rotors, and individual rotor blades can be separately attached to the hub. For this purpose, the hub is provided with a receptacle for the rotor blade fastening section of the rotor blade. Such blade fastening sections are generally formed in a cylinder and are provided with a transition region to a profile rotor blade section that interacts with the flow field and has a high structural stability. For this purpose, reference is made, for example, to US Pat. Cylindrical blade fastening sections typically have a diameter that is less than the chord length of the immediately adjacent profile rotor blade section and greater than the thickness of the profile in this region. Thus, there is a constriction from which the notch effect creates an event that loads the rotor blades, and this constriction must be protected by additional structural reinforcement.

The present invention is based on the object of identifying a rotor assembly for an axial turbine with a plurality of individually attachable rotor blades, which provides high structural stability of the rotor blade fasteners as well as adjacent drive shafts. Identified by efficient force and torque transmission. In addition, the rotor blade design is desired to allow easy replacement of individual rotor blades. Furthermore, the rotor assembly is particularly suitable for implementing an axial turbine that can be used to operate a tidal power plant and can preferably have a bidirectional input flow. The rotor arrangement must be able to mitigate particularly asymmetric load peaks that only act on the individual rotor blades and must be simplified in both design and manufacture. Furthermore, a method for attaching such a rotor blade assembly is sought.

Preferably, for a rotor capable of having a bi-directional input flow, not only is circumferential pressure between the blade fastening sections mediated, but rather there is additional traction and axial force components in the circumferential direction. Alleviated by the removable connection of adjacent blade fastening sections. Screw connections and / or formfitting connections are preferably considered as removable connections, and in the case of plant maintenance, the individual rotor blades can be adjusted or replaced separately. For an advantageous embodiment, the blade fastening section forms a split hub portion after performing the attachment to the drive shaft for interaction with individual adjacent blade fastening sections.

With respect to the preferred embodiment, the connection between the rotor blade and the drive shaft is made at the axial end face of the rotor blade fastening section, facing the axial end face of the drive shaft in the mounting position. Due to the input flow to the rotor blades, in particular shear loads are generated in the axial direction, resulting in a force component in the circumferential direction of the contact area of the adjacent blade fastening section. For this reason, with respect to an advantageous embodiment of the invention, each blade fastening section comprises a first contact area and a second contact area, and a third contact area as described above in contact with the drive shaft. The first contact area and the second contact area are preferably spatially divided. The first contact region and the second contact region are alternately adjacent to each other and are coupled to each other.

For improvement, it is conceivable to mediate a removable connection between the blade fastening sections of adjacent rotor blades with additional intermediate elements. However, for known hub components, these do not form a unitary structure, but rather are implemented as separate components arranged in a spatially divided manner. Due to the improvement of the invention, these intermediate elements can be adapted to the mounting arrangement of the rotor blades for the individual positions. This makes it possible to change the hit angle of the profile rotor blade section by the use of standardized rotor blades and the corresponding selection of rotor blade geometry, in particular intermediate elements.

1 is a perspective view illustrating a first exemplary embodiment of a rotor assembly according to the present invention in a partially mounted state. FIG. FIG. 7 is a perspective view illustrating a second exemplary embodiment of a rotor assembly according to the present invention in a partially mounted state. FIG. 6 is an axial plan view showing an alternative rotor design. FIG. 4 is an enlarged view showing details of FIG. 3. 4 shows a rotor assembly according to the invention with the rotor according to FIG. 3 attached to a drive shaft. FIG. FIG. 5 is an axial plan view showing a further alternative rotor design.

Each blade fastening section 4.1, 4.2, 4.3 comprises a first shaft end face 24 and a second shaft end face 25, which are formed by plate-like elements spaced from each other. The plate-like elements are connected by an end plate, which is in the first contact area 7.1, 7.2, 7.3 and in the second contact area 8.1, 8.2, 8.3. In the attached state, it extends in the axial section of the drive shaft 1 and is a lightweight structure but has a torsion-resistant structure, and is easily accessible for attachment work through the side opening 32 of the box structure. Has contributed.

In the mounted state, the first contact areas 7.1, 7.2, 7.3 for the first rotor blades 2.1, 2.2, 2.3 are directly adjacent individual rotor blades 2.1, 2.2, 2.3 facing the second contact areas 8.1, 8.2, 8.3 of the blade fastening sections 4.1, 4.2, 4.3. The first contact areas 7.1, 7.2, 7.3 and the second contact areas 8.1, 8.2, 8.3 facing each other in the installed state are the blade fastening section in the circumferential direction 23 Used for mutual support of 4.1, 4.2, 4.3.

FIG. 2 illustrates the improvement of the present invention with respect to a rotor assembly capable of having bi-directional input flow, alternating compressive and traction forces outlined by force components 29.3, 29.4. In order to alleviate this, fastening means are provided in the first contact areas 7.1, 7.2, 7.3 and the second contact areas 8.1, 8.2, 8.3. The dovetail-shaped fastening elements 10.1 to 10.5 are shown as examples for this purpose, they are already installed components of the individual rotor blades 2.1, 2.2, 2.3 The axial movement with respect to the blade allows the integral connection of the blade fastening sections 4.1, 4.2, 4.3. Bolts are used as removable connections for the additional blade fastening sections 4.1, 4.2, 4.3. The fastening element 6 is shown in FIG. 2 as an example for this purpose.

Further, with respect to the preferred embodiment shown, side opening 31 is provided in blade engagement section 4.2, 4.3 of the box-shaped, and reduce the weight of the rotor blade mounting part, for mounting, shaft Bore holes 17.1-17 used for mounting parts. It is clear from FIG. 4 that it allows access to n.

In the mounted state, the blade fastening sections 4.1, 4.2, 4.3 of the rotor blades 2.1, 2.2, 2.3 removably connected to one another are centrally open with respect to the advantageous embodiments. A divided hub portion 5 having a region 14 is formed. With respect to the embodiment shown in FIG. 3, the central open region 14 is triangular with respect to the sections in the rotor plane. Such a central open area 14 of the split hub part 5 deviating from the circle is such that after all the rotor blades 2.1, 2.2, 2.3 of the rotor 20 have been mounted successively, This allows the form fit connection to be pressed against the complementary shaft connection 16 of the drive shaft 1. This is shown in FIG. 5 as a plan view of the second shaft end face 25 of the rotor 20. Borehole 17.1-17. The hidden first shaft end surface 24 with n (not shown in FIG. 5) is pressed against the shaft end surface 26 of the drive shaft 1 for fastening. Rotor 20 which is mounted in this embodiment is capable of Rukoto partially mounted for maintenance purposes, the individual rotor blades 2.1, 2.2, 2.3 for the component parts of a further rotor, or Separately exchanged or readjusted with respect to the relative arrangement with respect to the drive shaft 1. For this purpose bore holes 17.1-17. It is conceivable that n allows a predetermined degree of freedom of attachment by a method using a long hole. For the sake of improvement (details not shown), a fixing element removably connected to the drive shaft 1 is adjacent to the shaft connection 16 and the fixing element is in the mounted position in the blade fastening sections 4.1, 4 and 4 2. Cover the second shaft end surface 25 of 4.3, and fix in the axial direction.

Claims (12)

A drive shaft (1) with an assigned axis of rotation (21) defining an axial direction (22) and a circumferential direction (23);
A rotor (20) with a plurality of rotor blades (2.1, 2.2, 2.3), each rotor blade having a profile rotor blade section (3) having an input flow in the axial direction (22) ., 3.2, 3.3) and a blade fastening section (4.1, 4.2, 4.3), and a rotor (20),
Comprising
Each blade fastening section (4.1, 4.2, 4.3) has a first contact area (7.1, 7.2, 7.3) and a second contact area (8.1, 8.2, 2). 8.3), wherein the first contact region (7.1, 7.2, 7.3) is the blade fastening section (4.1, 4.2, 4.. 3) is supported at least indirectly, and the second contact area (8.1, 8.2, 8.3) is adjacent to the second rotor blade (2.1, 2.2, 2.3). A rotor assembly supported at least indirectly by the blade fastening section (4.1, 4.2, 4.3) of
Said blade fastening section (4.1, 4.2, 4.3) is connected to said drive shaft (1) by means of a form-fit connection and / or using a screw connection (17.1 to 17.n) And the connection between the rotor blade and the drive shaft is made at the shaft end surface of the blade fastening section facing the shaft end surface of the drive shaft in the assembled position;
For each rotor blade (2.1, 2.2, 2.3), the profile rotor blade section (3.1, 3.2, 3.3) to the blade fastening section (4.1, 4.2, 2) 4.3) The rotor blade assembly, characterized in that the transition to (3) has a constricted outer contour.   Said blade fastening section (4.1, 4.2, 4.3) or blade fastening section (4.1, 4.2, 4.3) and intermediate element (13.1, 13.2, 13.3) The rotor blade assembly according to claim 1, characterized in that the whole forms a split hub part (5) of the rotor (20).   The first contact area (7.1, 7.2, 7.3) and the second contact area (8.1, 8.2, 8.3) are respectively adjacent to the rotor blade (2. 1, 2.2, 2.3) is removably connected to the blade fastening section (4.1, 4.2, 4.3), said removable connection being a screw connection and / or a form fit connection The rotor blade assembly according to claim 1, wherein the rotor blade assembly is implemented as follows.   The first contact area (7.1, 7.2, 7.3) and the second contact area (8.1, 8.2, 8) of the blade fastening section (4.1, 4.2, 4.3). .3) are arranged individually in the intermediate blade region (18.1, 18.2, 18.3) and between the adjacent rotor blades (2.1, 2.2, 2.3). 2. The rotor blade assembly according to claim 1, wherein an offset angle of the intermediate blade region in the circumferential direction with respect to the dividing surface is at most ± 30 °.   An intermediate element (13.1, 13.2, 13.3) with an elastic intermediate layer (12.1, 12.2, 12.3) is placed adjacent to the rotor blade (2.1, 2.2, The rotor blade assembly according to any one of claims 1 to 4, characterized in that it is provided between the blade fastening sections (4.1, 4.2, 4.3) of 2.3).   The rotor (20) comprises a plurality of separate intermediate elements (13.1, 13.2, 13.3) which are arranged in a spatially divided manner and adjacent to the blade fastening section (4. The rotor blade assembly according to any one of claims 1 to 5, characterized in that it forms a detachable connection of 1, 4.2, 4.3).   For each rotor blade (2.1, 2.2, 2.3), the assigned profile rotor blade section (3.1, 3.2, 3.3) and the assigned blade fastening section (4 7. The rotor blade assembly according to claim 1, wherein the rotor blade assembly is substantially coupled to the rotor blade assembly.   A blade stamp forming a first part of the profile rotor blade section (3.1, 3.2, 3.3) is substantially on each blade fastening section (4.1, 4.2, 4.3). 8. The second portion of the profile rotor blade section (3.1, 3.2, 3.3) is removably connected to the blade stamp. The rotor blade assembly according to any one of the preceding claims.   9. The blade fastening section (4.1, 4.2, 4.3) surrounds a central open area (14) of the rotor (20). The described rotor blade assembly.   The rotor blade assembly according to claim 9, wherein the contour of the second central open region (14) in the rotor plane deviates from a circular contour. A drive shaft (1) with an assigned axis of rotation (21) defining an axial direction (22) and a circumferential direction (23);
Profile rotor blade sections (3.1, 3) comprising a plurality of rotor blades (2.1, 2.2, 2.3), each rotor blade having an input flow in the axial direction (22) ., 3.3) and blade fastening sections (4.1, 4.2, 4.3), the profile rotor blade section (3.1, 3... 2, 3.3) to the blade fastening section (4.1, 4.2, 4.3) the rotor (20) with a constricted outer contour;
Comprising
Each blade fastening section (4.1, 4.2, 4.3) has a first contact area (7.1, 7.2, 7.3) and a second contact area (8.1, 8.2, 2). 8.3), wherein the first contact region (7.1, 7.2, 7.3) is the blade fastening section (4.1, 4.2, 4.. 3) and is guided to support at least indirectly, the second contact area (8.1, 8.2, 8.3) being adjacent to the second rotor blade (2.1, 2.. 2, 2.3) is guided to at least indirectly support the blade fastening section (4.1, 4.2, 4.3),
Said blade fastening section (4.1, 4.2, 4.3) is connected to said drive shaft (1) by means of a form-fit connection and / or using a screw connection (17.1 to 17.n) Fastened and the connection between the rotor blade and the drive shaft is made at the shaft end face of the blade fastening section facing the shaft end face of the drive shaft in the assembled position. A method for assembling a rotor assembly.   Said blade fastening section (4.1, 4.2, 4.3) or said blade fastening section (4.1, 4.2, 4.3) and intermediate element (13.1, 13.2, 13.3) 12) are arranged so that they form a split hub part (5) of the rotor (20).

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