EP3309359B1 - Blade assembly for a gas turbine engine - Google Patents

Description

The invention relates to a blade assembly for an engine with a ring or disc-shaped blade carrier with a plurality of blades.

Such a blade assembly is for example part of a compressor or a turbine of the engine, in particular of a gas turbine engine. The blades are thereby provided along a circular line about a central axis of the blade assembly, which central axis usually coincides with a rotational or central axis of the engine. The blade carrier, on which the blade is integrally formed or are fixed to the separately manufactured blades via a respective blade root, has a with respect to the blades radially inwardly in the direction of the central axis extending support portion. This support portion usually forms a part of a disk body, which - taking into account the available space - is formed comparatively large area in order to withstand the loads occurring during operation of the engine caused by the rapid rotation of the blade assembly about the central axis. The higher the speed of rotation of the blade carrier with the blades and thus the load on the blade carrier, the larger the carrier portion and consequently the weight of the blade carrier.

From the DE 101 63 951 C1 and DE 102 18 459 B3 For reducing the weight of a blade assembly and a rotor comprising it, it is proposed to provide a stiffening structure with first and second stiffening elements of a metal matrix composite ("MMC") on the blade carrier at a connection region of the carrier portion , Depending on a stiffening element is designed as a fiber reinforced MMC ring and arranged on a respective end face of the blade carrier. Thus, for example, two MMC rings are defined in mirror image at a connecting region of a radially inwardly extending support section of a blade carrier, namely on a first front end side and on a second rear end side of the blade carrier. Due to the additional stiffening elements in the form of the MMC rings, the blade carrier can be acted on with a smaller radial extension of the carrier section with higher rotational speeds and thus higher load capacity. In this case, the weight of the blade carrier is significantly lower than with a blade carrier of the same load carrying capacity with a larger carrier section through the MMC rings.

In the in the DE 101 63 951 C1 and DE 102 18 459 B3 proposed blade assemblies, the stiffening elements in the form of MMC rings are independently of each other positively fixed to one end face of the support portion and optionally additionally shrunk onto an axially extending projection of the connecting portion. Each MMC ring is axially secured separately on the respective end face of the support section and arranged on a radially outwardly facing transverse direction above the associated axially extending projection on the connection region of the support section. The fixation and in particular axial securing of the individual stiffening elements in the form of the MMC rings is thus comparatively complicated. Furthermore, the manufacture of the blade carrier with the connecting region, which is additionally intended to integrate a positive axial securing possibility, is complicated and associated with relatively high costs.

Other comparable blade assemblies go from the US 5,660,526 A , the US 3,610,777 A and the US 1,325,208 A out.

The invention is therefore based on the object to provide an improved in this respect blade assembly, with which the aforementioned disadvantages are avoided or at least reduced.

This object is achieved with a blade assembly of claim 1.

Accordingly, a rotor blade assembly for an engine having a ring-shaped or disc-shaped blade carrier having a plurality of blades is proposed, in which a stiffening structure is provided which has at least one stiffening element on a first or second end face of the blade carrier. In this case, the connecting region forms at least one axial projection, which is part of a cross-sectionally T-shaped, I-shaped or fir-tree-shaped profile of the connecting region and is encompassed by the at least one stiffening element, so that the axial projection at least partially between a radially outer and a radially inner portion of the stiffening element is received.

Consequently, an axially projecting portion of the connecting region extends between a radially outer and a radially inner portion of the stiffening element. In this case, an axial projection of the connection region can basically extend essentially parallel to the central axis and therefore essentially perpendicular to a radially extending end face of the carrier section. However, the axial projection can also assume a deviating from 90 ° angle to the front side.

Furthermore, a transition region between a substantially radially extending end-face support surface at the connection region and one end of the projection integrally formed therewith may be concavely curved. The degree of curvature and thus the course of a straight line to this transition region can be chosen differently depending on the engine and / or position of the blade assembly, depending on how strong the forces occurring at the connection area and with which force components, for example, this run radially and tangentially , For example, a straight line extends at the transition regions at an angle of 0 ° to 45 ° to the radial direction. The degree of curvature and thus the included angle can be done, for example, depending on the manufacturing material used for the stiffening element. In particular, with respect to a metal matrix composite and the fibers provided herein, which are circumferentially more resilient about the central axis than in a tangential direction, a smaller angle and thus a stronger concave curvature may result for the transition region (and thus a less softer "Transition between face and projection) offer.

The axial projection may in this case be e.g. locally ridge-like protruding or circumferentially annular to be formed on the connecting portion and be received for example between the two portions of the stiffening element in a groove-shaped recess of the stiffening element. The positive encircling an axial projection of the connecting region through at least one of the stiffening elements not only allows an improved force introduction into and support by the respective stiffening element, but also an improved connection of the respective stiffening element to the connecting region of the blade carrier. As a result, the stiffening element can be simply pushed or pushed axially onto the end face of the blade carrier and onto the at least one axial projection, for example, and is held radially secured on the blade carrier via the positive encompassing of the axial projection.

In a T-shaped profile, two projections extending axially in opposite directions are integrally formed at the connecting portion. Accordingly, in an I-shaped, i.e. cross-sectional profile of a double-T beam, there are two radially spaced pairs of such two axially extending projections in opposite directions. In a fir tree-shaped profile, at least two or three pairs arranged radially one above the other and spaced apart from each other are provided in opposite directions of axially extending projections, the axial extent of which gradually decreases or increases along a radial direction.

In a variant embodiment, a T-shaped, I-shaped or fir-tree-shaped profile of the connection region extends at least in sections along a circular line around the central axis. In a further development, the connecting region of the ring-shaped or disc-shaped blade carrier is provided with a T-shaped, I-shaped or fir-tree-shaped profile that completely surrounds the circumference.

In particular, in the case of a fir-tree-shaped cross-sectional profile of the connecting region, it is possible to arrange, for example, an annular reinforcing element on each end face of the blade carrier, which is provided with a correspondingly corresponding cross-sectional profile as a counterpart and engages around a plurality of axial projections, which are defined by the fir-tree-shaped cross-sectional profile of the connecting region. About such a connection between a respective stiffening element and the Connecting region of the blade carrier, the radial loads occurring during operation of the engine can be introduced more efficiently from the blade carrier in the stiffening structure. Here, the forces are also introduced at different radial locations in the stiffening structure and thus distributed, so that the power transmission between the blade carrier and the stiffening structure is improved. The connection and secure fixation of the stiffening structure on the blade carrier is considerably simplified.

In one possible development, sealing elements and / or cooling openings can be provided on an axial projection of the connection region, in particular on an axial projection of a T-shaped, I-shaped or fir-tree-shaped cross-sectional profile of the connection region. Cooling openings are then used, for example, to supply cooling air to the blade carrier.

In one embodiment variant, a rotor blade assembly for an engine with a ring-shaped or disc-shaped blade carrier with a plurality of rotor blades is provided, in which at least two stiffening elements, ie, at least one first stiffening element and at least one second stiffening element, a stiffening structure fixed to a connecting region of a carrier section of a blade carrier not only connected to the connection area, but the first and second stiffening elements are also additionally connected to each other.

As a result of the additional connection of the stiffening elements arranged on different end sides of the blade carrier, an axial securing of the stiffening elements to each other and to the blade carrier is achieved without each individual stiffening element itself having to be axially secured separately on the carrier section of the blade carrier. This embodiment is based on the basic idea that at the connection region of the blade carrier - preferably to a radially extending with respect to the central axis transverse direction symmetrically configured and opposing - stiffening elements are arranged on opposite first and second end faces of the blade carrier, by their additional connection with each other axially (relative to the central axis) are secured.

The axial securing of both stiffening elements of the stiffening structure is in this case in an embodiment variant via at least one separate connecting element of Realized stiffening structure, which connects the two arranged on different end sides of the stiffening elements directly together and axially secured against each other. In this way, none of the stiffening elements should be axially displaceable relative to the other stiffening element. Both stiffening elements are thus held in an intended position on the support portion.

The solution according to the invention is basically independent of whether the blades are formed integrally with the blade carrier and the blade assembly is thus manufactured in bling or blisk construction or the blades are made separately and fixed to the blade carrier. In one embodiment, for example, the annular or disc-shaped blade carrier is equipped with a plurality of individual blades, which are fixed in each case via a blade root of a blade on the blade carrier.

An above-mentioned separate connecting element for the connection of the first and second stiffening elements arranged on different end faces of the blade carrier with one another extends in a variant through a passage opening in the support section. This passage opening may be a central passage opening, for example in the form of a bore, through the blade carrier. The at least one separate connecting element then extends, for example, through such a central passage opening of the blade carrier in order to fix the two reinforcing elements axially relative to one another.

In particular, in this case, the at least one separate connecting element at least partially surround the first and second stiffening elements, so that at least parts of both stiffening elements are received in a cross section along the central axis between two sections of the connecting element. The connecting element is, for example, U-shaped in cross-section, so that both stiffening elements arranged on different end sides of the blade carrier are accommodated at least partially between two radially projecting limbs or edges of the connecting element.

Alternatively or additionally, the at least one connecting element may be formed as a clamping part which is held positively and / or non-positively on both first and second stiffening elements and respectively on the first or second stiffening element arranged on the connecting area in the direction of the other, second or first Stiffening element acting force exerts. About the clamping part thus the stiffening elements are clamped against each other, for example. The clamping part itself is in this case held positively and / or non-positively on both first and second stiffening elements, for example by engaging an extension of the clamping member in an opening or groove in the respective stiffening element or vice versa by the engagement of a lateral extension of the respective stiffening element in an opening or Groove of the clamping part.

In one embodiment, it is provided that the at least one stiffening element is annular. In a further development, interconnected first and second stiffening elements are each formed annularly. The annular design of a single stiffening element per end face has over several, for example, ring-segment-shaped stiffening elements per end face the advantage of easier and faster installation.

To reduce weight, the at least one stiffening element is at least partially made of a metal matrix composite material ("metal matrix composite", in short: "MMC") in one embodiment variant. In this case, the at least one stiffening element may comprise an externally sheathed core of a metal matrix composite material. The core may for example consist of a reinforced MMC-type titanium, that is, in particular of a titanium matrix with ceramic reinforcement.

In one embodiment variant, the blade carrier has a center passage extending axially, for example a central passage opening, which is bounded radially by an inner edge of the carrier section. A portion of the at least one stiffening element formed from a metal matrix composite material extends axially below this inner edge of the support section. Accordingly, it is provided in such a variant that the radially inner edge of the support section, which surrounds the preferably centrally provided passage opening in the annular or disc-shaped blade carrier is at least partially enclosed by the at least one stiffening element, for example, is bordered in an L-shaped cross-section , And a portion of the stiffening element extends with respect to a radially outwardly facing transverse direction below the connection region. The portion formed of a metal matrix composite material of the stiffening element arranged on the first or second end side therefore extends here below the inner edge in the direction of the other end face and consequently provides a Support below this inner edge by the metal matrix composite ready. The extension of the metal matrix composite material in the axial direction below an inner edge of the carrier section can thus serve for additional support underneath the rotor blades and the circumferentially revolving blade row formed therewith and lead to a more robust stiffening structure.

In addition to a positive encompassing of an axial projection of the connecting region, the blade carrier may have a passage opening extending axially with respect to the central axis, which is radially delimited by an inner edge of the carrier section, and at least one stiffening element of the stiffening structure may have at least one section below this inner edge of the stiffening structure Axially extend connection area. The at least one stiffening element of the stiffening structure thus extends here with at least one section axially on the inner edge of the connecting area along an end face in the direction of the other end face of the blade carrier. Regardless of the use of a metal matrix composite - and particularly regardless of the design discussed above, where a portion of the metal matrix composite stiffener extends axially below an inner edge - the extent of the stiffener beneath the radially inner edge of the blade carrier may be limited an improved support and stiffening of the blade carrier can be achieved in the region of the support section.

The formation of at least one axial and by a stiffening element positively encompassed connecting portion as well as the axial extent of at least a portion of the at least one stiffening element below an inner edge of the connecting portion to improve the mountability of the stiffening structure and the load capacity of the blade carrier are otherwise advantageous with an additional connection of combined on different end faces of the blade carrier arranged first and second reinforcing elements, but nevertheless also independently of this feasible.

With a blade assembly according to the invention, in particular, a gas turbine engine can be provided in which one or more blade rows of a compressor and / or one or more rows of blades of a turbine compared to previously common in practice blade rows are considerably reduced in weight, but the assembly of the stiffening structure and their axial fuse is comparatively easy. in this connection can each be a blade row forming blade assemblies arranged according to the invention thereto stiffening structures arranged axially one behind the other and rotationally fixed to each other. Of course, however, a combination of an inventively designed blade assembly for the formation of a blade row with another, not inventively designed blade assembly of another blade row is possible.

The attached figures exemplify possible embodiments of the invention.

Figur 1

ausschnittsweise und in Schnittdarstellung einen Teil einer Turbine eines Gasturbinentriebwerks mit zwei Ausführungsvarianten einer erfindungsgemäßen Laufschaufelbaugruppe;

Figuren 2A-2C

in vergrößerter Darstellung ausschnittsweise einen Verbindungsbereich eines Schaufelträgers mit unterschiedlichen Varianten einer hieran angeordneten Versteifungsstrukturen mit MMC-Versteifungsringen;

Figuren 3A-3B

ausschnittsweise und in geschnittener perspektivischer Ansicht Ausführungsvarianten eines Schaufelträgers einer erfindungsgemäßen Laufschaufelbaugruppe mit einem tannenbaumförmigen Profil des Verbindungsbereiches, wobei der Schaufelträger einerseits integral hiermit ausgebildete Laufschaufeln (Figur 3A) aufweist und andererseits für separat hergestellte und hieran zu fixierende Laufschaufeln vorgesehen ist (Figur 3B);

Figur 4

in geschnittener und vergrößerter Ansicht eine Variante eines Verbindungsbereichs des Schaufelträgers mit tannenbaumförmigem Profil;

Figur 5

ausschnittsweise und in geschnittener Darstellung eine aus dem Stand der Technik bekannte Ausbildung von Laufschaufelreihen einer Turbine eines Gasturbinentriebwerks;

Figuren 6

eine Querschnittsansicht eines Turbofan-Triebwerks, bei dem eine Ausführungsvariante einer erfindungsgemäßen Laufschaufelbaugruppe im Bereich eines Verdichters und/oder im Bereich einer Turbine zum Einsatz kommt.

Hereby show:

FIG. 1

a partial and sectional view of a portion of a turbine of a gas turbine engine with two embodiments of a blade assembly according to the invention;

Figures 2A-2C

in an enlarged view fragmentary a connecting portion of a blade carrier with different variants of a stiffening structures arranged thereon with MMC stiffening rings;

Figures 3A-3B

Sectionally and in a sectional perspective view of embodiments of a blade carrier of a blade assembly according to the invention with a fir-tree-shaped profile of the connection region, wherein the blade carrier on the one hand integrally formed herewith blades ( FIG. 3A ) and on the other hand provided for separately manufactured and thereto to be fixed blades ( FIG. 3B );

FIG. 4

in a sectioned and enlarged view of a variant of a connecting portion of the blade carrier with fir-tree-shaped profile;

FIG. 5

a section and a sectional view of a known from the prior art training of blade rows of a turbine of a gas turbine engine;

FIGS. 6

a cross-sectional view of a turbofan engine, in which an embodiment of a blade assembly according to the invention in the region of a compressor and / or in the region of a turbine is used.

The FIG. 6 illustrates schematically and in section a gas turbine engine T, in which the individual engine components along a rotational axis or center axis M are arranged one behind the other and the engine T is designed as a turbofan engine. At an inlet or intake E of the engine T, air is drawn in along an inlet direction R by means of a fan F. This arranged in a fan housing FC fan F is driven by a rotor shaft S, which is rotated by a turbine TT of the engine T in rotation. In this case, the turbine TT adjoins a compressor V, which has, for example, a low-pressure compressor 11 and a high-pressure compressor 12, and possibly also a medium-pressure compressor. On the one hand, the fan F supplies air to the compressor V and, on the other hand, a secondary flow channel or bypass channel B for generating the thrust. The bypass channel B in this case extends around a compressor V and the turbine TT comprehensive core engine, which includes a primary flow channel for the supplied through the fan F the core engine air.

The air conveyed into the primary flow passage via the compressor V enters a combustion chamber section BK of the core engine in which the driving power for driving the turbine TT is generated. For this purpose, the turbine TT has a high-pressure turbine 13, a medium-pressure turbine 14 and a low-pressure turbine 15. In this case, the turbine TT drives the rotor shaft S and thus the fan F via the energy released during the combustion in order to supply the required thrust via the air conveyed into the bypass duct B. produce. Both the air from the bypass passage B and the exhaust gases from the primary flow passage of the core engine flow through an outlet A at the end of the engine T. The outlet A in this case usually has a discharge nozzle with a centrally arranged outlet cone C.

Both in the area of the (axial) compressor with its low-pressure compressor 11 and its high-pressure compressor 12 and in the area of the turbine TT, rotating blade assemblies are known to be used about the central axis M, each having a blade row and in which the blades on a ring-shaped or disc-shaped Blade carrier are provided. The ring-shaped or disk-shaped blade carrier can in principle be integrally bladed and thus be manufactured in bling or blisk construction. Alternatively, the fixing of individual blades via their respective blade root on a ring-shaped or disk-shaped blade carrier is possible. For this purpose, for example, a blade root is inserted axially into a mounting groove of the blade carrier and axially secured to the respective blade carrier.

Based on FIG. 5 By way of example, a plurality of rotor blade assemblies 2a, 2b and 2c of the turbine TT arranged one behind the other along the central axis M are illustrated. The Indian FIG. 5 shown section shows only a part above the central axis M in the region of the medium-pressure turbine 14 or the low-pressure turbine 15. The individual blade assemblies 2a, 2b and 2c are non-rotatably connected via flange 4.1 and 4.2 together. Furthermore, each blade assembly 2a, 2b and 2c each have an annular or disc-shaped blade carrier 23, 24 or 25, on the individual blades 20, 21 or 22 of a blade row along a circular line about the central axis M arranged one behind the other and on the respective blade carrier 23, 24 or 25 via a blade root 200, 210 or 220 of a blade 20, 21 or 22 are fixed. In the axial direction along the central axis M while blade rows of blade assemblies 2a, 2b and 2c alternate with fixed vanes rows. The guide blade rows each have guide vanes 30 or 31, which are also peripherally arranged circumferentially along a circular line about the central axis M.

Due to the high speeds and concomitant loads, each blade carrier 23, 24 or 25 of a prior art blade assembly 2a, 2b or 2c has a radially inwardly extending beam portion 230, 240 or 250. A disk-shaped support portion 250 of the rear blade assembly 2c serves, for example, for the rotatable mounting of the rotatably connected blade assemblies 2a, 2b and 2c. In the support section 230, 240 two related in the flow direction through the engine T - front blade assemblies 2a and 2b, a central through hole O1 or O2 is provided primarily for weight reduction, for example in the form of a bore. With regard to the necessary installation space of the blade assemblies 2a and 2b and their weight, it is above all decisive which radial extent the blade carriers 23 and 24 have in order to be able to withstand the loads occurring during operation.

In the different variants of a solution according to the invention, for example, in the FIG. 1 by way of example on two blade assemblies 2a and 2b of the turbine TT, a clear reduction of the radially extending carrier sections 230 or 240 is achieved by the provision of a stiffening structure 5a or 5b. Here are the two different variants in the FIG. 1 illustrated together. However, it is not mandatory to provide different stiffening structures 5a and 5b on one blade assembly 2a and another blade assembly 2b. In order to simplify the assembly and the use of the largest possible number of identical parts, it will be practical to use identically configured stiffening structures 5a or 5b on different blade assemblies 2a and 2b.

Common to the different in the FIG. 1 However, each illustrated variants of stiffening structures 5a and 5b that two opposing annular stiffening elements in the form of (MMC) stiffening rings 50 and 51 at the end faces of the respective blade carrier 23 or 24 are arranged. The stiffening rings 50 and 51 are on the one hand directly connected to each other - preferably via at least one additional connecting element. On the other hand, both stiffening rings 50, 51 each surround a connection region 231 or 241 of the respective support section 230 or 240 in a form-fitting manner at least in sections, which has a profile which is continuous in the circumferential direction and has at least two projections extending axially in opposite directions. In one variant of the blade assembly 2a, the connection region 231 is provided with a fir-tree-shaped (cross-sectional) profile, while in the case of the other blade assembly 2b the FIG. 1 a T-shaped cross-sectional profile is provided.

As based on the FIGS. 2A, 2B and 2C is illustrated for different variants of the stiffening structures 5a, 5b, each stiffening ring 50, 51 of the respective stiffening structure 5a or 5b, a sheathed MMC core 500, for example, a TiMMC core. About the production of the stiffening rings 50 and 51 In MMC design, a considerably increased rigidity of the blade carrier 23 or 24 is achieved with a comparatively low weight. In each of the variants of FIGS. 2A, 2B and 2C extends a stiffening ring 50 or 51 with a Umgriffabschnitt 50.1 or 51.2 axially below one of the respective passage opening O1 or O2 facing edge of the connecting portion 231 or 241 in the direction of the other end face. A radially inner edge of the respective blade carrier 23 or 24 is thus encompassed by each stiffening ring 50 or 51 at least partially L-shaped. As a result, in particular the radial securing of the respective stiffening ring 50, 51 on the support section 230 or 240 is facilitated and a support of the blade carrier 23, 24 below the connection region 231, 241 is achieved

In the present case, both stiffening rings 50 and 51, each with an encompassing section 50.1 or 51.2, extend axially below the inner edge of the carrier section 231 or 241 of the blade carrier 23 or 24 such that the stiffening rings 50 and 51 abut one another directly via their encompassing sections 50.1 and 51.2. The stiffening rings 50 and 51 provided on both sides of the connecting portion 231 or 241, which are each held in a form-fitting manner to the respective connecting portion 231 or 241, are thus immediately adjacent to each other and the stiffening structure 5a or 5b formed therewith extends completely through the through-hole O1 or O2.

By virtue of the stiffening structure 5a or 5b with the stiffening rings 50 and 51 arranged on the end faces of the blade carrier 23 or 24 facing away from one another, radially acting forces can be absorbed in particular. By circumferentially encircling profiling of the connecting portion 231 or 241 but at the same time simpler installation and simple radial securing of the blade carrier 23 or 24 to be mounted stiffening rings 50 and 51 is given.

In a fir-tree-shaped cross-sectional profile corresponding to the variants of FIGS. 2A and 2B The connecting region 231 exemplarily illustrated here forms pairs of projections 2310.1 / 2310.2, 2311.1 / 2311.2 and 2312.1 / 2312.2 that extend in opposite directions. Each of these axial projections 2310.1 to 2312.2 protrudes annularly on an end face of the support portion 230. To form the fir-tree-shaped profile, the axial length of the individual axial projections 2310.1 to 2312.1 or 2310.2 to 2312.2 per end face decreases in the radial direction, in the present case radially inwards. Accordingly, a pair of axial protrusions 2312.1 / 2312.2 closest to the through hole O1 have the least axial Extension on and radially further outwardly arranged pairs of axial projections 2311.1 / 2311.2 and 2310.1 / 2310.2 each axially further.

At the individual stiffening rings 50 and 51 are provided with the projections 2310.1 to 2312.1 or 2310.2 to 2312.2 one end side corresponding grooves, so that the respective mounted on an end side stiffening ring 50 or 51 each projection 2310.1 to 2312.1 or 2310.2 to 2312.2 engages positively on the respective end side and consequently each projection 2310.1 to 2312.2 is respectively received between a radially further inward and radially further outward portion of the respective stiffening ring 50 or 51. By thus formed positive connection between the blade carrier 23 and the stiffening rings 50 and 51 radial loads occurring in the operation of the engine T are distributed over the fir-tree-shaped profile in the stiffening structure 5a introduced. In addition, the stiffening structure 5 a on the support section 230 of the blade carrier 23 is already radially fixed by attaching the stiffening rings 50, 51 without additional fastening means.

For axial fixation of the two stiffening rings 50 and 51 is at least one in the FIGS. 2A and 2B not shown in detail connecting element provided. By way of such a connecting element, the two stiffening rings 50 and 51 are additionally connected directly to one another, so that an undesired displacement and in particular a separation of the stiffening rings 50 or 51 from the blade carrier 23 in the axial direction is prevented. Each stiffening ring 50 or 51 is also held on the other stiffening ring 51 or 50 via the at least one connecting element, whereby a displacement is prevented relative thereto.

For example, a single connection element can be used. In a variant, this individual connection element may extend annularly around the stiffening structure 5a or at least over a large part of a radially inner circumference of the stiffening structure 5a. Alternatively, a plurality of local connection elements for axial securing along the circumference can be provided offset from one another.

For example, a connecting element 6 is formed with a U-shaped cross section, as shown in the Figure 2C for the stiffening structure 5b is shown, wherein such a connecting element 6 also in the stiffening structure 5a of FIGS. 2A and 2B can be used. Such a connecting element 6 is via two legs or edges 60, 61 of the connecting element 6 positively and / or non-positively connected to two stiffening rings 50 and 51. For fixing the connecting element 6 to the mutually symmetrically designed stiffening rings 50, 51 a narrow groove in each edge or legs 60, 61 is provided, in each of which an extension in the form of a circumferentially extending, axially projecting edge or nose of the respective stiffening ring 50, 51 engages.

In the cross-sectional view, both stiffening rings 50 and 51 are received between the two legs or edges 60, 61 of the connecting element 6. In this case, a force can be exerted on each of the stiffening rings 50, 51, which presses the stiffening ring 50, 51 in the direction of the other stiffening ring 51 or 50 via the two end-side engaging and radially extending edges or legs 60, 61. The connecting element 6 thus acts as a clamping part, which biases the two stiffening rings 50 and 51 axially against one another.

In the embodiment of the Figure 2C is unlike the variants of the FIGS. 2A and 2B the connecting portion 241 provided with no fir-tree-shaped profile, but with a T-shaped profile. The connection area 241 of the Figure 2C Thus, there are two protrusions 2410.1 and 2410.2 projecting axially in opposite directions. These are each in this variant, each form-fitting embraced by the associated, arranged on the respective end side reinforcing ring 50 or 51.

In the variants of the FIGS. 2B and 2C It is further provided that the respective MMC core 500 of a stiffening ring 50 or 51 extends with at least a portion 500.1 or 500.2 of the metal matrix composite material below the inner edge of the support portion 230 or 240. In the variant of FIG. 2B For example, the MMC core is substantially L-shaped in cross-section. In the variant of Figure 2C For example, the MMC core 500 of each stiffening ring 50 or 51 is C-shaped in cross-section. In the variant of FIG. 2A Thus, the MMC core 500 is only axially adjacent to the connection region 231 and in particular adjacent to the projections 2310.1 to 2312.2 arranged. In the variant of FIG. 2B By contrast, the MMC core 500 is arranged axially next to the connection region 231 and at least partially below the connection region 231 and consequently in particular adjacent to the projections 2310.1 to 2312.2 and at least partially below the projections 2310.1 to 2312.2. Due to the C-shaped cross section, a respective section 500.3 or 500.4 of the MMC core 500 is additionally arranged above a projection 2410.1 or 2410.2 and consequently there is an axial projection 2410.1 or 2410.2 of the respective front or rear End face between two sections 500.1 / 500.3 or 500.2 / 500.4 of the metal matrix composite material.

With the FIGS. 3A and 3B Two different variants of the blade carrier 23 of the blade assembly 2a are illustrated. In both variants, the blade carrier 23 has a fir-tree-shaped cross-sectional profile extending in the circumferential direction on the connection region 231 for the stiffening structure 5a and its stiffening rings 50 and 51 to be attached here. While in the variant of FIG. 3A the blade carrier 23 is formed with blades 20 integrally formed thereon, the blade carrier 23 has the FIG. 3B a plurality of circumferentially arranged side by side mounting grooves 232 for thereto to be fixed blade roots 200 of the blades 20.

Based on the cross-sectional representation of FIG. 4 is further exemplified with respect to a fir-tree-shaped profile of the connecting portion 231 of a blade carrier 23, via which design parameters, if necessary, the connection between the blade carrier 23 and the stiffening rings 50, 51 and thus the power transmission can be influenced in the stiffening structure 5a. For example, in the present case, a radius Ra is shown for a transition area between a radially extending end face of the support section 230 and a radially outermost projection 2310.1 of an end face, the size of which influences the degree of concavity of the transition area.

A geometry of the fir-tree-shaped profile can also be characterized by an angle α, the two tangents to each other, which are each applied in a cross-sectional view along the central axis M to the ends of the axial projections 2310.1 to 2312.1 or 2310.2 to 2312.2 an end face. The greater the angle α, the greater the axial extent of the fir-tree-shaped profile and / or the greater the gradation in the axial extent between the projections 2310.1 to 2312.1 or 2310.2 to 2312.2 provided on an end face.

LIST OF REFERENCE NUMBERS

11

Low-pressure compressor

12

High-pressure compressors

13

High-pressure turbine

14

Intermediate pressure turbine

15

Low-pressure turbine

20, 21, 22

blade

200, 210, 220

blade

23, 24, 25

blade carrier

230, 240, 250

support section

231

connecting area

2310.1, 2310.2, 2311.1, 2311.2, 2312.1, 2312.2

Axial projection

232

mounting groove

241

connecting area

2410.1, 2410.2

Axial projection

2a, 2b, 2c

Blade assembly

30, 31

vane

4.1, 4.2

flange

50, 51

Stiffening ring (stiffening element)

50.1, 51.2

Umgriffabschnitt

500

MMC core

500.1, 500.2, 500.3, 500.4

MMC Section

5a, 5b

stiffening structure

6

Clamping part (connecting element)

60, 61

frontal edge / thigh

A

outlet

B

bypass channel

BK

combustor section

C

exit cone

e

Inlet / Intake

F

fan

FC

fan casing

M

Central axis / rotation axis

O1, O2

Through opening

R

entry direction

Ra

radius

S

rotor shaft

T

Turbofan engine (gas turbine engine)

TT

turbine

V

compressor

α

corner

Claims (13)

1. Rotor blade assembly group for an engine (T) with a ring-shaped or disc-shaped blade carrier (23, 24) having multiple rotor blades (20, 21) that are provided along a circle line about a central axis (M) of the rotor blade assembly group (2a, 2b), wherein

   - the blade carrier (23, 24) has a carrier section (230, 240) that extends radially inwards in the direction of the central axis (M) with respect to the rotor blades (20, 21),

   - the carrier section (230, 240) comprises a connection area (231, 241) at which a stiffening structure (5a, 5b) with at least one stiffening element (50, 51) is fixedly attached, and

   - the stiffening element (50, 51) is arranged at a first or second face side of the blade carrier (23, 24),
   characterized in that
   the connection area (231, 241) forms at least one axial projection (2310.1-2312.2; 2410.1-2410.2) that is part of the profile of the connection area (231, 241) which has a T-shaped, I-shaped or firtree-shaped cross section and around which the at least one stiffening element (50, 51) engages in a form-fit manner, so that the axial projection (2310.1-2312.2; 2410.1-2410.2) is at least partially received between a radially outer and a radially inner section of the stiffening element (50, 51).
2. Rotor blade assembly group according to claim 1, characterized in that the profile of the connection area (231, 241) that has a T-shaped, I-shaped or firtree-shaped cross section extends along a circle line about the central axis (M) at least in certain sections.
3. Rotor blade assembly group according to claim 1 or 2, characterized in that

   - the stiffening structure (5a, 5b) that is fixedly attached at the connection area (231, 241) has at least one first stiffening element (50) and at least one second stiffening element (50),

   - the first stiffening element (50) is arranged at a first face side of the blade carrier (23, 24) and the second stiffening element (51) is arranged at a second face that is facing away from the first face side, and

   - the first and second stiffening elements (50, 51) are connected to the connection area (231, 241) of the blade carrier (23, 24) and additionally also to each other.
4. Rotor blade assembly group according to claim 3, characterized in that the first and second stiffening elements (50, 51), which are arranged at different face sides of the blade carrier (23, 24), are connected to each other via at least one separate connection element (6) of the stiffening structure (5a, 5b).
5. Rotor blade assembly group according to claim 4, characterized in that the at least one separate connection element (6) extends through a passage hole (O1, O2) inside the carrier section (230, 240).
6. Rotor blade assembly group according to claim 4 or 5, characterized in that the at least one separate connection element (6) engages around the first and second stiffening elements (50, 51), so that at least parts of both stiffening elements (50, 51) are received between two sections (60, 61) of the connection element (6) in a cross section along the central axis (M).
7. Rotor blade assembly group according to one of the claims 4 to 6, characterized in that the at least one connection element is formed as a tensioning part (6) that is supported at both first and second stiffening elements (50, 51) in a form-fit and/or force-fit manner, and respectively exerts a force on the first or second stiffening element (50, 51) that is arranged in the connection area (231, 241), which is acting in the direction of the other, second or first, stiffening element (51, 50).
8. Rotor blade assembly group according to one of the preceding claims, characterized in that the at least one stiffening element (50, 51) is formed in a ring-shaped manner.
9. Rotor blade assembly group according to one of the preceding claims, characterized in that the at least one stiffening element (50, 51) is manufactured at least partially from a metal matrix composite.
10. Rotor blade assembly group according to claim 9, characterized in that the at least one stiffening element (50, 51) has an externally coated core (500) made of a metal matrix composite.
11. Rotor blade assembly group according to claim 9 or 10, characterized in that the blade carrier (23, 24) has a passage hole (O1, O2) that extends axially with respect to the central axis (M) and that is radially delimited by an inner edge of the carrier section (230, 240), and a section of the at least one stiffening element (50, 51) that is made of a metal matrix composite axially extends radially inside with respect to the inner edge of the connection area (231, 241).
12. Rotor blade assembly group according to one of the preceding claims, characterized in that the blade carrier (23, 24) has a passage hole (01, 02) that extends axially with respect to the central axis (M) and that is radially delimited by an inner edge of the carrier section (230, 240), and the at least one stiffening element (50, 51) of the stiffening structure (5a, 5b) axially extends radially inside with respect to the inner edge of the connection area (231, 241) with at least one section (50.1, 51.2).
13. Gas turbine engine with at least one rotor blade assembly group (2a, 2b) according to any of the claims 1 to 12.

Images