Fibre composite component for the rotor blade of a wind turbine

Abstract

A composite fiber component for a rotor blade of a wind power plant including a first sandwich core and a second sandwich core arranged next to each other, each having an inside facing a rotor blade interior and an outside facing a rotor blade exterior. A first fiber-containing laminate layer is arranged on the inside of the first sandwich core and on the outside of the second sandwich core. A second fiber-containing laminate layer is arranged on the outside of the first sandwich core and on the outside of the second sandwich core. And, a third fiber-containing laminate layer is arranged on the inside of the first sandwich core and on the inside of the second sandwich core. Also disclosed is a rotor blade for a wind power plant having a composite fiber component as disclosed.

Claims

1. A rotor blade of a wind power plant, said rotor blade having an aerodynamic profile with a suction side and a pressure side, wherein, in a transition region opposite to a profile nose, the rotor blade includes a profile trailing edge that is defined by a closing-off web arranged transversely to a profile chord, wherein the closing-off web transitions to the suction side and to the pressure side, respectively, at transitional edges, wherein at least at one of the transitional edges of the rotor blade comprises a first sandwich core arranged next to a second sandwich core, wherein the first sandwich core and the second sandwich core each have an inside facing a rotor blade interior and an outside facing a rotor blade exterior, wherein a first fiber-containing laminate layer is arranged on the inside of the first sandwich core and on the outside of the second sandwich core, wherein a second fiber-containing laminate layer is arranged on the outside of the first sandwich core and on the outside of the second sandwich core, wherein a third fiber-containing laminate layer is arranged on the inside of the first sandwich core and on the inside of the second sandwich core, wherein the first sandwich core and the second sandwich core are arranged at an angle with respect to one another in a region where the first fiber-containing laminate layer passes between them, wherein said angle is defined by the outside of the first sandwich core and the outside of the second sandwich core at the transitional edge, and wherein said angle lies in a range between 25 and 165.

2. The rotor blade as claimed in claim 1, wherein the rotor blade comprises at least two rotor blade shells.

3. The rotor blade as claimed in claim 1, wherein at least one of the first fiber-containing laminate layer, the second fiber-containing laminate layer and the third fiber-containing laminate layer comprises at least one ply of fiber material which is embedded in a matrix of cured matrix material.

4. The rotor blade as claimed in claim 3, wherein each of the first fiber-containing laminate layer, the second fiber-containing laminate layer and the third fiber-containing laminate layer comprises at least one ply of fiber material which is embedded in a matrix of cured matrix material.

5. The rotor blade as claimed in claim 3, wherein the rotor blade comprises at least two rotor blade shells.

6. The rotor blade as claimed in claim 3, wherein the first fiber-containing laminate layer, the second fiber-containing laminate layer and the third fiber-containing laminate layer have a common matrix of cured matrix material.

7. The rotor blade as claimed in claim 6, wherein the rotor blade comprises at least two rotor blade shells.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention is described below, without the general idea of the invention being restricted, by means of exemplary embodiments with reference to the drawings, while, in regard to all the particulars of the invention not explained in any more detail in the text, reference is made expressly to the drawings in which:

(2) FIG. 1 shows diagrammatically a near-hub region of a rotor blade according to the invention;

(3) FIG. 2 shows diagrammatically a sectional illustration of the rotor blade according to the invention along the line A-A in FIG. 1;

(4) FIG. 3 shows diagrammatically a sectional illustration of the sandwich laminate of the rotor blade according to the invention along the line B-B in FIG. 1, and

(5) FIG. 4 shows diagrammatically a sectional illustration of the sandwich laminate of the rotor blade according to the invention along the line C-C in FIG. 1.

(6) In each case identical or similar elements and/or parts are given the same reference numerals in the drawings, and therefore there is no need in each case to introduce them again.

DETAILED DESCRIPTION OF THE INVENTION

(7) FIG. 1 shows diagrammatically the near-hub region of a rotor blade 1 according to the invention.

(8) The rotor blade has a blade root 12 of round cross section for connecting the rotor blade 10 to a hub of a wind power plant. Behind the blade root 12 along the longitudinal extent of the rotor blade 10, the rotor blade 10 has in cross section an aerodynamic profile which varies with the distance from the blade root 12. Only at some distance, for example a plurality of meters, behind the blade root 12 does the rotor blade 10 have an aerodynamic profile with a trailing edge 14 tapering to a point. By contrast, in the transitional region lying in front, the rotor blade 10 has an aerodynamic profile with a profile end face, in particular with a truncated trailing edge, that is to say the aerodynamic profile terminates or is closed off by a closing-off web 16 arranged transversely to the profile chord.

(9) FIG. 2 shows diagrammatically a sectional illustration of the rotor blade 10 in this region along the line A-A illustrated in FIG. 1.

(10) The load-bearing structure of the rotor blade 10 comprises two girders 17 which, together with two webs 18, form a stable box structure. The outer envelope of the rotor blade 10 comprises rotor blade shells 19, 19 which are connected, for example glued, to the load-bearing structure composed of the girders 17 and of the webs 18. Alternatively, for example, the girders 17 may be integrated into the rotor blade shells 19, 19.

(11) Typically, at least two rotor blade shells, the bottom shell 19 on the pressure side and the top shell 19 on the suction side of the rotor blade, are provided. It is in this case unimportant for the invention whether the rotor blade shells 19, 19 extend in one piece over the entire length of the rotor blade 10 or are composed of a plurality of rotor blade part shells.

(12) The flow impinges upon the rotor blade 10 in the region of the profile nose 13. Located at that end of the aerodynamic profile which is at the rear in the flow impingement direction is a sheet-like closing-off web 16 arranged transversely to the profile chord.

(13) In the example shown of a rotor blade 10 according to the invention, the bottom shell 19 and the closing-off web 16 are integral parts of a common composite fiber component 20 in a sandwich laminate type of construction.

(14) FIG. 3 shows the set-up of the sandwich laminate of the composite fiber component 20 in a diagrammatic sectional illustration along the line B-B in FIG. 1.

(15) The composite fiber component 20 comprises a first sandwich core 31 for the bottom shell 19 and a second sandwich core 32 for the closing-off web 16. The sandwich cores 31, 32 comprise, for example, laths or boards made of balsa wood and are of essentially sheet-like form. Thus, in each case, an inside 23 of the sandwich cores 31, 32 faces the rotor blade interior 22 and an outside 25 of the sandwich cores 31, 32 faces the rotor blade exterior 24.

(16) The sandwich cores 31, 32 are arranged next to one another at an angle to one another, a gap remaining between the sandwich cores 31, 32. The sandwich core 31 is of wedge-shaped form at the margin, so that the gap between the sandwich cores 31, 32 arranged at an angle to one another has an essentially constant gap width.

(17) The sandwich laminate of the composite fiber component 20 comprises, furthermore, a plurality of laminate layers 34, 35, 36. Of these, there is an inner laminate layer 34 which runs in each case over the inside 23 of the two sandwich cores 31, 32. Furthermore, an outer laminate layer 35 is provided, which runs in each case over the outsides 25 of the two sandwich cores 31, 32. A third laminate layer 36 runs between the inside 23 of the sandwich core 31 for the bottom shell 19 and the inner laminate layer 34, continues in the gap between the sandwich cores 31, 32 and then runs between the outside 25 of the sandwich core 32 for the closing-off web and the outer laminate layer 35.

(18) The three laminate layers 34, 35, 36 comprise in each case one or more plies of fiber material, for example mats made from glass fibers. The fiber plies of the laminate layers 34, 35, 36, illustrated diagrammatically as unbroken lines in FIG. 3, and also the two sandwich cores 31, 32 are embedded in a common resin matrix 38 of cured resin, the surface contours of which are illustrated as dashed lines in FIG. 3. The surface contours of the resin matrix 38 at the same time form the surfaces of the composite fiber component toward the rotor blade interior 22 and toward the rotor blade exterior 24.

(19) FIG. 4 shows diagrammatically a sectional illustration of the composite fiber component 20 in a sectional plane which lies nearer to the blade root 12 and which is illustrated in FIG. 1 by the line C-C.

(20) The set-up of the sandwich laminate of the composite fiber component 20 with two sandwich cores 31, 32 and with three laminate layers 34, 35, 36 corresponds, in principle, to the set-up shown in FIG. 3. However, some differences emerge in detail.

(21) Near the blade root 12, the sandwich cores 31, 32 are arranged at a much flatter angle to one another in order to achieve a uniform transition into the round blade root 12. To form a gap having an essentially constant gap width, both sandwich cores 31, 32 are of wedge-shaped form at the margin in this region. The third laminate layer 36 consequently extends at a flat angle from the inside 23 of the first sandwich core 31 to the outside 25 of the second sandwich core 32, this having a positive effect upon the stability of the connection between the two sandwich cores 31, 32.

(22) Furthermore, to increase mechanical stability, both the sandwich cores 31, 32 and the laminate layers 34, 35, 36 are designed to be thicker at the transition to the blade root 12 than in that region of the fiber composite component 20 which is illustrated in FIG. 3.

(23) All the features mentioned, also the features to be gathered from the drawings alone as well as individual features which are disclosed in combination with other features are considered as essential to the invention either alone or in combination. Embodiments according to the invention may be fulfilled by means of individual features or a combination of a plurality of features.

LIST OF REFERENCE SYMBOLS

(24) 10 rotor blade

(25) 12 blade root

(26) 13 blade nose

(27) 14 trailing edge

(28) 16 closing-off web

(29) 17 girder

(30) 18 web

(31) 19 bottom shell

(32) 19 top shell

(33) 20 composite fiber component

(34) 22 rotor blade interior

(35) 23 inside

(36) 24 rotor blade exterior

(37) 25 outside

(38) 31, 32 sandwich core

(39) 34, 35, 36 laminate layer

(40) 38 resin matrix