Patent Description:
As the demands for blades for wind turbines tends towards blades of increasing lengths, attention is increasing on concepts of manufacturing blades in sections, e.g. for being assembled at the installation site. Such wind turbine blade, comprising a plurality of sections, may be known as a split blade, or two-part blade, or segmented blade or similar.

However, several challenges are associated with such design, relating to the manufacturing and joining of the shell segments including how to join the shells of the succeeding sections without compromising aerodynamic performance and/or generation of undesirable increased noise.

Furthermore, it may be important to seal such joint between segments in order to prevent rain, dust, or other things from the outside environment from entering into the wind turbine blade, potentially causing damages to interior components of the wind turbine blade.

Furthermore, as a segmented wind turbine blade will often or always be assembled in the field, e.g. at the erection site. It is also of interest to provide solutions to facilitate easy and simple assembly of the wind turbine blade.

Similar challenges may be found in other industries, and the solutions provided below may thus be applicable also in assembly of sections of structures other than wind turbine blades or wind turbines. Examples of prior art solutions can be found in documents <CIT>, <CIT>, <CIT> and <CIT>.

It is an object of the present disclosure to provide elements and methods for supporting the assembly and performance of a segmented structure, in particular to facilitate the assembly and performance of a segmented wind turbine blade.

Accordingly, a sealing member is disclosed, such as a sealing member for sealing a joint between sections of a structure, such as a joint between a first blade section and a second blade section of a wind turbine blade, wherein the second blade section is coupled to the first blade section. The sealing member has a first surface and a second surface. The sealing member has a width between a first edge and a second edge. The sealing member is configured for attachment to a first outer surface, such as a first outer shell of the first blade section, along the first edge, and for attachment to a second outer surface, such as a second outer shell of the second blade section, along the second edge. The sealing member comprises a corrugated section between the first edge and the second edge. The corrugated section comprises one or more valleys and/or ridges extending along a lengthwise direction of the sealing member.

Also disclosed is a wind turbine blade comprising a first blade section and a second blade section coupled to the first blade section. The first blade section extending along a longitudinal axis from a root to a first end, the first blade section comprising a root region and a first airfoil region. The first blade section comprising a first outer shell terminating at the first end. The second blade section extending along the longitudinal axis from a second end to a tip, the second blade section comprising a second airfoil region, the second blade section comprising a second outer shell terminating at the second end. The wind turbine blade comprises a sealing member, such as the sealing member as disclosed above, e.g. to seal a joint between the first blade section and the second blade section. The sealing member has a first surface and a second surface. The sealing member has a width between a first edge and a second edge. The sealing member is attached to the first outer shell along the first edge, and the sealing member is attached to the second outer shell along the second edge. The sealing member comprises a corrugated section between the first edge and the second edge. The corrugated section comprises one or more valleys and/or ridges extending along a lengthwise direction of the sealing member.

Also disclosed is a method for sealing a joint between sections of a structure, such as a joint between a first blade section and a second blade section of a wind turbine blade, wherein the second blade section is coupled to the first blade section, such as a wind turbine blade as disclosed above. The first blade section extending along a longitudinal axis from a root to a first end, the first blade section comprising a root region and a first airfoil region. The first blade section comprising a first outer shell terminating at the first end. The second blade section extending along the longitudinal axis from a second end to a tip, the second blade section comprising a second airfoil region. The second blade section comprising a second outer shell terminating at the second end.

After positioning the sections of the structure in their respective positions, e.g. after coupling and positioning the first blade section and the second blade section in their respective position to form the wind turbine blade, the method comprises: Providing a sealing member, such as the sealing member as disclosed above, having a first surface and a second surface, the sealing member having a width between a first edge and a second edge, the sealing member comprising a corrugated section between the first edge and the second edge, the corrugated section comprising one or more valleys and/or ridges extending along a lengthwise direction of the sealing member; and applying the sealing member to the joint between the first blade section and the second blade section. Applying the sealing member comprises: Attaching the sealing member to a first outer surface, such as the first outer shell, along the first edge; and attaching the sealing member to a second outer surface, such as the second outer shell along, the second edge.

Optionally, prior to applying the sealing member to the joint, the method comprises cleaning a first shell bond area of the first outer shell and/or cleaning a second shell bond area of the second outer shell. Cleaning the first shell bond area and/or the second shell bond area may comprise e.g. abrasing and/or cleaning using solvent. Alternatively or additionally, the cleaning may comprise wiping the first shell bond area and/or the second shell bond area dry, e.g. using a dry cloth.

Although the present disclosure is mainly describing utilizing the disclosed sealing member in relation to sealing of a joint between sections of a wind turbine blade, it will be realised that the disclosed sealing member and the method of sealing a joint using the sealing member may be used in sealing of joints of other structures, such as automotive parts, aircraft parts, watercraft parts, robotics, machinery etc..

It is an advantage that a flexible and non-bespoke sealing member is provided, and that a joint may be sealed, e.g. preventing ingress or egress of liquids and/or debris to/from a cavity, in a simple and easy procedure.

It is a further advantage of the present disclosure that the joint may be sealed from the outside, e.g. after the sections forming the joints have been attached and respectively positioned. Hence, the present disclosure provides an easier and more convenient method for sealing a joint between sections of a structure.

It is a further advantage of the present disclosure that an amount of flexibility is provided in the sealing member, such as to allow some degree of compression and/or expansion, such as to prevent or reduce the risk of failure.

Furthermore, it is an advantage of the present disclosure, that in the case of sealing a joint of a wind turbine blade, the disclosure provides a sealing member and a method for sealing a joint, which may maintain aerodynamic performance of the wind turbine blade, while avoiding or reducing transfer of significant loads between blade shell ends. In a preferred embodiment, the sealing member allows for not more than <NUM>% load transfer, such as not more than <NUM>% load transfer, between the first blade section and the second blade section. It is thus preferred that the major part, such as at least <NUM>% or at least <NUM>%, or all of the load transfer between the first blade section and the second blade section is via the one or more spar beams. Loads and moments are thus advantageously transferred from one blade section via the spar beam into the other blade section, rather than via the sealing member.

Furthermore, it is an advantage of the present disclosure, in particular in the case of sealing a joint of a wind turbine blade, that operational noise levels may be kept within acceptable limits.

Furthermore, it is an advantage of the present disclosure, that it may be provided to facilitate lightning protection of the structure, e.g. the wind turbine blade, and in particular of the joint.

The second surface of the sealing member may comprise bond areas configured to be bonded to exterior surfaces near the joint. The second surface of the sealing member may comprise a first bond area along the first edge. The first bond area may be configured to be bonded to the first outer shell. The second surface may comprise a second bond area along the second edge. The second bond area may be configured to be bonded to the second outer shell. For example, attaching the sealing member to the first outer shell along the first edge may comprise bonding together the first bond area and a first shell bond area of the first outer shell. Thus, the sealing member may be attached to the first outer shell of the wind turbine blade by the first bond area and a first shell bond area of the first outer shell being bonded together. Additionally or alternatively, attaching the sealing member to the second outer shell along the second edge may comprise bonding together the second bond area and a second shell bond area of the second outer shell. Thus, the sealing member may be attached to the second outer shell of the wind turbine blade by the second bond area and a second shell bond area of the second outer shell being bonded together. Bonding together the first bond area and the first shell bond area and/or bonding together the second bond area and the second shell bond area may be provided by gluing, welding etc. For example, the first bond area and the first shell bond area and/or the second bond area and the second shell bond area may be bonded together by glue, dual sided tape, adhesive etc..

The first edge and the second edge of the sealing member may be parallel, such as substantially parallel.

The sealing member has a corrugated section. The corrugated section may have a peak-to-peak height, e.g. between <NUM>-<NUM>, such as <NUM>.

The sealing member may have a thickness between the first surface and the second surface. The sealing member may have a generally uniform thickness between the first surface and the second surface. The sealing member may have a generally uniform thickness between the first surface and the second surface in the corrugated section. The thickness of the sealing member, such the thickness of the corrugated section of the sealing member, may be between <NUM>-<NUM>, such as <NUM>.

The sealing member may be an extruded member or a pultruded member. The sealing member may have a substantially constant cross-section along the lengthwise direction.

It is preferred that the material constituting the sealing member is different than the material constituting the first and second blade sections.

In a preferred embodiment, the sealing member has a lower stiffness than the first blade section and the second blade section. Similarly, it is preferred that the elastic modulus of the material forming the sealing member is lower than the elastic modulus of the material forming the first blade section and of the material forming the second blade section.

In a preferred embodiment, the sealing member is formed from a material having a modulus of elasticity (Young's modulus) of <NUM> MPa or less, preferably <NUM> MPa or less. In some embodiments, the sealing member has an elastic modulus (Young's modulus) of between <NUM> and <NUM> MPa, such as between <NUM> and <NUM> MPa. The skilled reader will understand that the elastic modulus, also known as Young's modulus, defines the relationship between stress (force per unit area) and strain (proportional deformation) in a material. Thus, the elastic modulus is a measure of the stiffness of a material. The elastic modulus can be determined by the cantilever beam test, as is well known in the art.

The sealing member may comprise a thermoplastic polyurethane, such as aliphatic thermoplastic polyurethane. In a preferred embodiment, the sealing member may be made of thermoplastic polyurethane, such as aliphatic thermoplastic polyurethane. The material of the sealing member may be chosen to provide for desired strength and/or flexibility of the sealing member. Furthermore, the material may be chosen to insulate against lightning, e.g. to enhance lightning protection of interior components of the structure, such as the wind turbine blade.

The sealing member may be reinforced, e.g. by including e-glass or aramid fibres in the sealing member. For example, one or more e-glass or aramid biaxial sheet(s) may be provided between layers of thermoplastic polyurethane to form the sealing member.

The sealing member may encircle the first outer shell of the first blade section and/or the second outer shell of the second blade section. For example, the sealing member may extend from a trailing edge of the wind turbine blade, along a suction side of the wind turbine blade, past a leading edge of the wind turbine blade, along a pressure side of the wind turbine blade, to the trailing edge of the wind turbine blade. One continuous piece of the sealing member may extend all the way around the outer shell(s) of the wind turbine blade. Thus, in a preferred embodiment, the sealing member is a single, continuous piece. It is particularly preferred that opposing ends of the single sealing member are joined, preferably at the trailing edge of the wind turbine blade, to provide a closed loop of the sealing member. In a preferred embodiment, the wind turbine blade comprises only one sealing member according to the present invention. It is particularly preferred that, the wind turbine blade comprises only one sealing member, the sealing member being composed of a unitary material throughout its extent. The unitary material may comprise polyurethane, such as thermoplastic polyurethane or fibre-reinforced thermoplastic polyurethane.

Applying the sealing member may comprise positioning the sealing member to encircle the first outer shell of the first blade section and/or the second outer shell of the second blade section. Applying the sealing member may comprise positioning the sealing member to extend from the trailing edge of the wind turbine blade, along the suction side of the wind turbine blade, past the leading edge of the wind turbine blade, along the pressure side of the wind turbine blade, to the trailing edge of the wind turbine blade. The sealing member may be applied in any suitable order, e.g. the sealing member may be applied to the suction side before being applied to the pressure side, or the sealing member may be applied to the pressure side before being applied to the suction side.

The sealing member may extend in the lengthwise direction from a first sealing member end to a second sealing member end. The lengthwise direction of the sealing member may be parallel to the first edge and/or parallel to the second edge. The first sealing member end may be attached to the second sealing member end. For example, the first sealing member end may be attached to the second sealing member end at the trailing edge of the wind turbine blade, e.g. applying the sealing member, e.g. to the joint, may comprise attaching the first sealing member end to the second sealing member end. For example, the sealing member may be applied to the joint of the wind turbine blade from the trailing edge, around the outer shell(s) and back to the trailing edge on the opposite side of the wind turbine blade, where the two ends of the sealing member, the first sealing member end and the second sealing member end may be attached to each other. Attaching the first sealing member end to the second sealing member end may comprise bonding together a first connecting area of the second surface at the first sealing member end and a second connecting area of the second surface at the second sealing member end.

The first sealing member end and the second sealing member end may be attached by attaching a first connecting area of the second surface at the first sealing member end to a second connecting area of the second surface at the second sealing member end. For example, the first sealing member end may be attached to the second sealing member end by bonding together, such as gluing or welding, such as heat welding, the first connecting area and the second connecting area.

The first sealing member end may be attached to the second sealing member end, e.g. at the trailing edge of the wind turbine blade, such that the first sealing member end and the second sealing member end protrudes from the wind turbine blade, e.g. from the trailing edge of the wind turbine blade. The first sealing member end and/or the second sealing member end may form a projecting sealing member part, e.g. projecting from the wind turbine blade, such as from the trailing edge of the wind turbine blade. The projecting sealing member part may be shaped to contribute to the aerodynamic performance of the wind turbine blade. For example, the projecting sealing member part may be tapered towards the first edge and/or the second edge of the sealing member. The projecting sealing member part may be rounded, curved, or triangular.

In a preferred embodiment, the sealing member has a substantially symmetrical cross section. It was found that such symmetrical cross section of the sealing member helps maintaining the aerodynamic performance of the wind turbine blade.

The wind turbine blade, such as the first blade section and/or the second blade section, such as the first outer shell and/or the second outer shell may be formed to allow attachment of the first sealing member end and the second sealing member end, with no or a limited projecting sealing member. For example, a gap between the first end and the second end may be increased near the trailing edge, e.g. to allow attachment of the first sealing member end and the second sealing member end through the gap. For example, the trailing edge of the first outer shell may comprise a first void section and/or the trailing edge of the second outer shell may comprise a second void section, e.g. such as to form the increased gap.

The sealing member may be positioned such that the lengthwise direction of the sealing member is in a plane substantially perpendicular to the longitudinal axis of the wind turbine blade. For example, applying the sealing member may comprise orientating the sealing member such that the lengthwise direction of the sealing member is in a plane substantially perpendicular to the longitudinal axis of the wind turbine blade. The sealing member may be positioned such that the lengthwise direction of the sealing member is orientated substantially parallel to a direction of expected airflow across the wind turbine blade when in operation, in particular expected airflow at the position of the sealing member. Such orientation of the sealing member provides that the valleys and/or ridges are parallel to the expected airflow, and thereby noise generated by the sealing member may be reduced.

The first end of the first blade section and the second end of the second blade section may be spaced apart to form a gap between the first end and the second end. For example, the gap may be formed between the first outer shell and the second outer shell. The sealing member may extend across the gap, e.g. when the sealing member is applied to the wind turbine blade, such as to the joint of the wind turbine blade. The corrugated section may be positioned in the gap, e.g. the corrugated section may be positioned between the first end and the second end.

The wind turbine blade may comprise a spar beam, such as a spar beam coupling the first blade section and the second blade section. The spar beam may longitudinally extend along a spar beam axis, e.g. from a first beam position, such as a first beam end, to a second beam position, such as a second beam end. The spar beam may be positioned such that the first beam position is located in the first airfoil region and the second beam position is located in the second airfoil region. A third beam position, e.g. between the first beam position and the second beam position, may be aligned with the first end of the first blade section and/or the second end of the second blade section.

Embodiments of the disclosure will be described in more detail in the following with regard to the accompanying figures. The figures show one way of implementing the present invention and are not to be construed as being limiting to other possible embodiments falling within the scope of the attached claim set.

<FIG> illustrates a conventional modern upwind wind turbine <NUM> according to the so-called "Danish concept" with a tower <NUM>, a nacelle <NUM> and a rotor with a substantially horizontal rotor shaft. The rotor includes a hub <NUM>, and three blades <NUM> extending radially from the hub <NUM>, each having a blade root <NUM> nearest the hub and a blade tip <NUM> furthest from the hub <NUM>.

The wind turbine blade <NUM> comprises a blade shell which may comprise two blade shell parts, a first blade shell part <NUM> and a second blade shell part <NUM>, typically made of fibre-reinforced polymer. The first blade shell part <NUM> is typically a pressure side or upwind blade shell part. The second blade shell part <NUM> is typically a suction side or downwind blade shell part. The first blade shell part <NUM> and the second blade shell part are typically glued together along bond lines or glue joints <NUM> extending along the trailing edge <NUM> and the leading edge <NUM> of the blade <NUM>. Typically, the root ends of the blade shell parts <NUM>, <NUM> has a semi-circular or semi-oval outer cross-sectional shape.

The wind turbine blade <NUM> extends along a longitudinal axis L. The root end <NUM> extends in a root end plane, substantially perpendicular to the longitudinal axis L.

The wind turbine blade <NUM> is a so-called split blade, or two-part blade, or segmented blade. The wind turbine blade <NUM> comprises a first blade section <NUM> and a second blade section <NUM>. The first blade section <NUM> extends along the longitudinal axis L from a root, such as the root end <NUM>, to a first end <NUM>. The second blade section <NUM> extends along the longitudinal axis L from a second end <NUM> to a tip, such as the tip end <NUM>. The first blade section <NUM> comprises a root region <NUM>, a first airfoil region 34a and a transition region <NUM> between the root region <NUM> and the first airfoil region 34a. The second blade section <NUM> comprises a second airfoil region 34b with the tip, such as the tip end <NUM>. The first blade section <NUM> and the second blade section <NUM> may be coupled with a spar beam (see <FIG>). The first blade section and the second blade section meet at a joint <NUM>.

<FIG> is a schematic diagram illustrating an exemplary wind turbine blade <NUM>, such as the wind turbine blade <NUM> of the previous figures. The wind turbine blade <NUM> comprises a first blade section <NUM>, a second blade section <NUM>, and a spar beam <NUM> for coupling the first blade section <NUM> and the second blade section <NUM>. The spar beam <NUM> may comprise carbon fibre, e.g. the spar beam <NUM> may comprise pultruded carbon fibre reinforced polymer.

The spar beam <NUM> extends, such as longitudinally extends, along a spar beam axis B, e.g. from a first beam position to a second beam position. The spar beam axis B may be coinciding and/or parallel with the longitudinal axis of the wind turbine blade <NUM>. When the wind turbine blade is assembled, the spar beam <NUM> extends from a point in the first airfoil region 34a to point in the second airfoil region 34b. For example, the spar beam <NUM> may be positioned such that the first beam position, e.g. a first end of the spar beam, is located in the first airfoil region 34a, and the second beam position, e.g. a second end of the spar beam, is located in the second airfoil region 34b. A third beam position, between the first beam position and the second beam position, may be aligned with the first end <NUM> of the first blade section <NUM> and/or the third beam position may be aligned with the second end <NUM> of the second blade section <NUM>.

<FIG> is a schematic diagram illustrating a cross section of the airfoil region of an exemplary wind turbine blade <NUM>, such as the wind turbine blade <NUM> of <FIG> and <FIG>. The wind turbine blade <NUM> comprises a trailing edge <NUM>, a leading edge <NUM>, a pressure side <NUM>, a suction side <NUM>, shear webs <NUM>, such as a trailing edge shear web 41a and a leading edge shear web 41b, and a chord line <NUM> running from the leading edge <NUM> to the trailing edge <NUM>. The shear webs <NUM> could, in an alternative wind turbine blade, be replaced by sides of a spar. Thus, although in the following, examples may be provided with reference to a wind turbine blade comprising shear webs, these could be replaced by sides of a spar. For example, the wind turbine blade <NUM> may have shear webs as shown in a first blade section, while the wind turbine blade may be supported by a spar beam in a second blade section, for example, as illustrated in <FIG>.

<FIG> is a schematic diagram illustrating an exemplary sealing member <NUM>, such as a sealing member <NUM> for sealing a joint, such as a joint between a first blade section and a second blade section of a wind turbine blade, e.g. as illustrated in the previous figures, wherein the second blade section is coupled to the first blade section.

The sealing member <NUM> has a first surface <NUM> and a second surface <NUM>. The sealing member <NUM> has a width D0 between a first edge <NUM> and a second edge <NUM>. The sealing member is configured for attachment to a first outer shell of the first blade section along the first edge <NUM>, and for attachment to a second outer shell of the second blade section along the second edge <NUM>,.

The sealing member <NUM> comprises a corrugated section <NUM> between the first edge <NUM> and the second edge <NUM>. The corrugated section comprises one or more valleys <NUM> and/or ridges <NUM> extending along a lengthwise direction of the sealing member <NUM>.

The cross section of the sealing member <NUM> may be substantially constant along the lengthwise direction. The sealing member <NUM> extends in the lengthwise direction from a first sealing member end <NUM> to a second sealing member end <NUM>. The first sealing member end <NUM> may be configured to be attached to the second sealing member end <NUM> such that the sealing member <NUM> may form a closed loop.

The second surface <NUM> comprises a first bond area <NUM> along the first edge <NUM>. The first bond area <NUM> is configured to be bonded to the first outer shell. The second surface <NUM> comprises a second bond area <NUM> along the second edge <NUM>. The second bond area <NUM> is configured to be bonded to the second outer shell.

<FIG> is a schematic diagram illustrating an exemplary sealing member <NUM>, such as the sealing member of the previous figures, being applied to a wind turbine blade, such as the wind turbine blade <NUM> as exemplified in relation to the previous figures. The sealing member <NUM> encircles the wind turbine blade, i.e. the sealing member <NUM> extends from the trailing edge <NUM>, along the suction side <NUM>, past the leading edge <NUM>, along a pressure side (not shown), to the trailing edge <NUM>. The sealing member <NUM> has a first end <NUM> and a second sealing member end (not shown), which meet and are attached to each other at the trailing edge <NUM> (see <FIG> for more details). The sealing member <NUM> has a first surface <NUM>, a second surface (not shown) facing the wind turbine blade outer shells, a first edge <NUM> and a second edge <NUM>. The sealing member is attached to the first outer shell <NUM> of the first blade section <NUM> along the first edge <NUM>. The sealing member <NUM> is attached to the second outer shell <NUM> of the second blade section <NUM> along the second edge <NUM>. The sealing member <NUM> is positioned such that the lengthwise direction of the sealing member is in a plane substantially perpendicular to the longitudinal axis L of the wind turbine blade <NUM>.

<FIG> is a schematic diagram illustrating a cross section of an exemplary sealing member <NUM>, such as the sealing member of the previous figures. The sealing member <NUM> has a first surface <NUM>, a second surface <NUM>, a first edge <NUM> and a second edge <NUM>. The sealing member <NUM> is attached to the first outer shell <NUM> of the first blade section <NUM> along the first edge <NUM> and the sealing member <NUM> is attached to the second outer shell <NUM> of the second blade section <NUM> along the second edge <NUM>. The second surface <NUM> comprises a first bond area <NUM> and a second bond area <NUM>. The sealing member may be attached by bonding together the first bond area <NUM> of the sealing member and a first shell bond area of the first outer shell <NUM>, and by bonding together the second bond area <NUM> of the sealing member and a second shell bond area of the second outer shell <NUM>. Bonding may comprise using e.g. gluing, welding, tape, adhesive. The sealing member <NUM> extends across joint <NUM> between the first end <NUM> of the first outer shell <NUM> and the second end <NUM> of the second outer shell <NUM>. In the illustrated example, the joint forms a gap, and the sealing member <NUM> extends across the gap between the first end <NUM> and the second end <NUM>. The gap of the joint <NUM>, e.g. the distance D4 between the first end <NUM> and the second end <NUM>, may be between <NUM>-<NUM>, such as <NUM>.

Between the first edge <NUM> and the second edge <NUM> is a corrugated section <NUM> comprising one or more valleys <NUM> and/or ridges <NUM>, which extend along a lengthwise direction of the sealing member <NUM>, e.g. the valleys <NUM> and/or ridges <NUM> extend parallel to the first edge <NUM> and/or the second edge <NUM>. The corrugated section <NUM> of the sealing member <NUM> is positioned in the gap of the joint <NUM>.

The sealing member has a thickness D1 between the first surface <NUM> and the second surface <NUM>. The thickness D1 may be uniform in the corrugated section and be between <NUM>-<NUM>, such as <NUM>.

The sealing member <NUM> has a peak-to-peak height D2, e.g. between the ridges <NUM> and valleys <NUM>. The height D2 may be between <NUM>-<NUM>, such as <NUM>.

The sealing member <NUM> has a distance D3 between valleys and/or ridges, e.g. a valley to ridge distance, e.g. between two valleys and/or two ridges. The distance D3 between valleys and/or ridges may be between <NUM>-<NUM>, such as <NUM>.

As seen in <FIG> and <FIG>, the sealing member <NUM> preferably has a substantially symmetrical cross section to help maintain the aerodynamic performance of the wind turbine blade.

<FIG> is a schematic diagram illustrating an exemplary sealing member <NUM>, such as the sealing member of the previous figures. <FIG> shows the first end <NUM> and the second end <NUM> of the sealing member <NUM>. The second surface <NUM> has a first bond area <NUM> for attaching to the first outer shell of the wind turbine blade and a second bond area <NUM> for attaching to the second outer shell of the wind turbine blade. The second surface <NUM> has a first connecting area <NUM> at the first end <NUM> of the sealing member and a second connecting area <NUM> at the second end <NUM> of the sealing member. The first end <NUM> and the second end <NUM> meet and attach to each other at the trailing edge of the wind turbine blade. The first end <NUM> and the second end <NUM> may be attached by bonding together the first connecting area <NUM> and the second connecting area <NUM>, e.g. by welding, such as heat welding.

<FIG> are schematic diagrams illustrating an exemplary sealing member <NUM>, such as the sealing member of the previous figures being applied to a joint of a wind turbine blade <NUM> (only partly shown). <FIG> shows the sealing member <NUM> having a projecting sealing member part <NUM>. The first sealing member end <NUM> and/or the second sealing member end <NUM> may form the projecting sealing member part <NUM>. The first sealing member end <NUM> and the second sealing member end <NUM> may be attached together at the projecting sealing member part <NUM>. The projecting sealing member part <NUM> may be caused by the first sealing member end <NUM> and the second sealing member end <NUM> being attached together, e.g. to allow heat welding of the first sealing member end <NUM> together with the second sealing member end <NUM>.

<FIG> shows the sealing member <NUM> being applied to the first outer shell <NUM> of the first blade section <NUM> and the second outer shell <NUM> of the second blade section <NUM>, such that the sealing member <NUM> is attached to the first outer shell <NUM> along a first edge <NUM> of the sealing member and the sealing member <NUM> is attached to the second outer shell <NUM> along a second edge <NUM> of the of the sealing member <NUM>.

The projecting sealing member part <NUM> may project from the wind turbine blade <NUM>, such as from the trailing edge <NUM> of the wind turbine blade as illustrated. Furthermore, the projecting sealing member part <NUM> may be shaped in various shapes, e.g. to contribute to the aerodynamic performance of the wind turbine blade <NUM>. For example, the projecting sealing member part <NUM> may be tapered towards the first edge <NUM> as illustrated in <FIG> Alternatively or additionally, the projecting sealing member part <NUM> may be tapered towards the second edge <NUM> as illustrated in <FIG>. The projecting sealing member part <NUM> may be rounded or curved, or triangular.

The projecting sealing member part <NUM> may be shaped, e.g. by cutting the first sealing member end <NUM> and/or the second sealing member end <NUM> to form the desired shape, e.g. prior to attaching the first sealing member end <NUM> and the second sealing member end <NUM> and/or after attaching the first sealing member end <NUM> and the second sealing member end <NUM>.

<FIG> are schematic diagrams illustrating part of an exemplary wind turbine blade <NUM> having a first blade section <NUM> and a second blade section <NUM>, and the joint between the first blade section <NUM> and the second blade section <NUM> being sealed by a sealing member <NUM>, such as a sealing member <NUM> as described in relation to previous figures. <FIG> shows examples of the first outer shell <NUM> of the first blade section <NUM> and the second outer shell <NUM> of the second blade section <NUM> comprising void sections <NUM>, <NUM> at the trailing edge <NUM>. The trailing edge <NUM> of the first outer shell <NUM> comprises a first void section <NUM>. The trailing edge of the second outer shell <NUM> comprises a second void section <NUM>. The first void section <NUM> and the second void section <NUM> form an increased gap near the trailing edge <NUM>, to allow attachment of the first sealing member end <NUM> and the second sealing member <NUM> end through the gap. Thereby, a projecting sealing member end <NUM> as described in relation to <FIG>, may be avoided or at least reduced.

The void sections <NUM>, <NUM> may be provided in various shapes. The examples of <FIG>, show two different shapes, e.g. triangular void section <NUM>, <NUM> as illustrated in <FIG>, and trapezoid shaped void sections <NUM>, <NUM> as illustrated in <FIG>.

<FIG> is a flow diagram illustrating an exemplary method <NUM> for sealing a joint with an exemplary sealing member, such as a sealing member as described in relation to one or more of the previous figures. The joint may be between a first blade section and a second blade section of a wind turbine blade, such as a wind turbine blade as described in relation to the previous figures, wherein the second blade section is coupled to the first blade section.

The method <NUM> comprises, e.g. after coupling and positioning the sections forming the joint, such as after coupling and positioning the first blade section and the second blade section in their respective position to form the wind turbine blade, providing <NUM> a sealing member having a first surface and a second surface, the sealing member having a width between a first edge and a second edge, the sealing member comprising a corrugated section between the first edge and the second edge, the corrugated section comprising one or more valleys and/or ridges extending along a lengthwise direction of the sealing member.

The method <NUM> comprises applying <NUM> the sealing member to the joint between the first blade section and the second blade section. Applying <NUM> the sealing member comprises attaching <NUM> the sealing member to the first outer shell along the first edge. Applying <NUM> the sealing member comprises attaching <NUM> the sealing member to the second outer shell along the second edge.

The second surface comprises a first bond area along the first edge, and the second surface comprises a second bond area along the second edge. Attaching <NUM> the sealing member to the first outer shell along the first edge may comprise bonding 204b together the first bond area and a first shell bond area of the first outer shell. Attaching <NUM> the sealing member to the second outer shell along the second edge may comprise bonding 206b together the second bond area and a second shell bond area of the second outer shell.

The method <NUM> optionally comprises cleaning <NUM> a first shell bond area of the first outer shell and/or a second shell bond area of the second outer shell. Cleaning <NUM> the first shell bond area and/or the second shell bond area may comprise e.g. abrasing and/or cleaning using solvent. The cleaning <NUM> may comprise wiping 208b the first shell bond area and/or the second shell bond area dry, e.g. using a dry cloth. Cleaning <NUM> the first shell bond area and the second shell bond area may be performed prior to applying <NUM> the sealing member to the joint.

The method <NUM> optionally comprises, e.g. as part of applying <NUM> the sealing member, positioning <NUM> the sealing member to extend from a trailing edge of the wind turbine blade, along a suction side of the wind turbine blade, past a leading edge of the wind turbine blade, along a pressure side of the wind turbine blade, to the trailing edge of the wind turbine blade.

The sealing member may extend in a lengthwise direction from a first sealing member end to a second sealing member end.

The method <NUM> optionally comprises, e.g. as part of applying <NUM> the sealing member, orientating <NUM> the sealing member such that the lengthwise direction of the sealing member is in a plane substantially perpendicular to the longitudinal axis of the wind turbine blade. For example, the sealing member may be positioned such that the lengthwise direction of the sealing member is substantially parallel to a direction of expected airflow across the wind turbine blade when in operation.

The method <NUM> optionally comprises, e.g. as part of applying <NUM> the sealing member, attaching <NUM> the first sealing member end to the second sealing member end, e.g. near the trailing edge of the wind turbine blade. For example, the first sealing member end and the second sealing member end may be attached <NUM> together, after having wound the sealing member around the outer shells of the wind turbine blade, and/or having attached <NUM>, <NUM> the sealing member to the first outer shell and the second outer shell.

Attaching <NUM> the first sealing member end to the second sealing member optionally comprises bonding together 214b, e.g. by heat welding, a first connecting area of the second surface at the first sealing member end and a second connecting area of the second surface at the second sealing member end.

Claim 1:
A wind turbine blade comprising a first blade section (<NUM>) and a second blade section (<NUM>) coupled to the first blade section,
the first blade section (<NUM>) extending along a longitudinal axis from a root to a first end, the first blade section comprising a root region and a first airfoil region, the first blade section (<NUM>) comprising a first outer shell terminating at the first end,
the second blade section (<NUM>) extending along the longitudinal axis from a second end to a tip, the second blade section (<NUM>) comprising a second airfoil region, the second blade section (<NUM>) comprising a second outer shell terminating at the second end,
the wind turbine blade comprising a sealing member (<NUM>) having a first surface and a second surface, the sealing member (<NUM>) having a width between a first edge and a second edge, the sealing member (<NUM>) being attached to the first outer shell along the first edge, and the sealing member being attached to the second outer shell along the second edge,
the sealing member (<NUM>) comprising a corrugated section (<NUM>) between the first edge and the second edge, the corrugated section comprising one or more valleys (<NUM>) and/or ridges (<NUM>) extending along a lengthwise direction of the sealing member (<NUM>).