WO2023117014A1

WO2023117014A1 - Transport or storage arrangement of a split wind turbine blade

Info

Publication number: WO2023117014A1
Application number: PCT/DK2022/050294
Authority: WO
Inventors: Joris KOFMAN; Morten Baungaard NIELSEN; Frank Hoelgaard Hahn
Original assignee: Vestas Wind Systems A/S
Priority date: 2021-12-22
Filing date: 2022-12-20
Publication date: 2023-06-29

Abstract

There is provided a nested transport or storage arrangement (34) for a split wind turbine blade (18), the split wind turbine blade comprising a plurality of longitudinally extending blade segments (24a, 24b) configured for end-to-end connection to form an assembled split wind turbine blade, wherein at least a second blade segment (24b) is stored inside a first blade segment (24a).

Description

T ransport or storage arrangement of a split wind turbine blade

Technical field

The present invention relates generally to wind turbine blade transportation and more specifically to a transportation or storage arrangement for a split wind turbine blade, and a method of arranging a split wind turbine blade for transport or storage.

Background

There is a continuing desire to generate increased amounts of power from wind power production facilities such as on-shore and off-shore wind farms. One way to achieve this is to eguip modern wind turbines with larger blades. The provision of larger blades increases the swept area of the rotor, allowing the wind turbine to capture more energy from the wind.

Wind farms are typically situated in remote locations which may be difficult to access. As such, transporting large wind turbine blades to a wind farm site can be problematic. In some cases, transport methods and access routes can place constraints on the size of wind turbine blades selected for a given wind farm. Some modern wind turbine blades are therefore designed as a split assembly comprising two or more longitudinal segments. The segments are transported separately before being assembled on-site at the wind farm location to form the wind turbine blade. Being of shorter length than the fully assembled blade, the respective segments of a split blade can provide a solution to the logistical challenges of transporting long blades in one piece. Such split wind turbine blades can thus offer the advantages of a large wind turbine blade whilst alleviating some of the issues with transportation of such large components. In the present context, the term split blade is applied to a blade having multiple longitudinal segments joined together at a chordwise interface. A longitudinal segment may also be understood as a spanwise segment. A split blade may also be known as a segmented blade or modular blade.

However, storing and transporting a large wind turbine blade in a plurality of separate segments also presents a number of other challenges. Despite being shorter than a singlepiece wind turbine blade, individual blade segments are still large components requiring specific storage and transport solutions. US8172493B2 discloses a transport arrangement for a multiple piece wind turbine blade in which a single blade may be captured in four frame elements, two of which are hinged together. The arrangement allows a lateral side- by-side transportation of the root and tip segments of a blade. In US8240962B2 there is disclosed a shipping arrangement for multiple segment blades in which each segment has two frames attached, and in which the segments may be arranged laterally side-by-side. Increasing blade size makes these side-by-side arrangements of the segments too wide for many transport routes and therefore impractical to implement, leaving the segments to be transported separately. However, transporting a blade in separate segments may increase the number of vehicles required for transporting the blade, causing an increase in CO2 and other emissions, and costs. Individually unloading a number of segments after transportation may also increase handling times. Further, transporting a greater number of wind turbine blade components may result in increased logistics and handling costs at each stage of the transportation process.

It is against this background that the present invention has been developed.

Summary of Invention

In a first aspect of the invention there is provided a nested transport or storage arrangement for a split wind turbine blade, in particular, for segments of a split wind turbine blade. The split wind turbine blade comprises a plurality of longitudinally extending blade segments configured for end-to-end connection to form an assembled wind turbine blade, wherein at least a second longitudinal blade segment is stored inside a first longitudinal blade segment. A nested split blade storage or transport arrangement per the present invention is defined in appended claim 1. Further optional features thereof are defined in subclaims 2- 13. Still further optional features are discussed in the foregoing description.

The first blade segment may be an inboard blade segment of a split wind turbine blade. The second blade segment may be an outboard blade segment of the split wind turbine blade. The terms inboard and outboard may be understood in relation to a hub of a horizontal wind turbine rotor, of which the blade is configured to form a part. In other words, an inboard blade segment may be configured to lie closer to the hub than an outboard blade segment. A portion of a blade which is directly connectable to a hub is sometimes known as a root portion. For present purposes, a most inboard blade segment may be referred to as a root segment. A segment of a blade which is furthest from a hub when the blade is fixed to a hub is sometimes known as a tip segment. A tip segment may thus be a most outboard segment. Additionally however, each segment has an inboard region and an outboard region; and an inboard end and an outboard end.

The second blade segment comprises an outboard segment of the split wind turbine blade, this being either a most outboard, tip, segment or an intermediate segment between a root segment and a tip segment. Preferably, a second blade segment may be a tip segment. Thus, a second blade segment may in particular comprise a tip end segment of the split wind turbine blade. The first blade segment comprises an inboard segment of the split wind turbine blade. As mentioned, a first blade segment may thus in particular comprise a root end of the split wind turbine blade. In other examples, the second blade segment may be an intermediate blade segment comprising neither of the root end or tip end of the split wind turbine blade. In some examples, the nested storage arrangement may comprise one or more outboard blade segments stored inside the first blade segment, which is an inboard blade segment relative to the blade segments nested inside it. In this arrangement, the first, inboard blade segment may be a root segment.

Preferably, the second blade segment extends longitudinally within the first blade segment. The second blade segment is preferably substantially aligned with the first blade segment in the nested storage arrangement. For example, a longitudinal axis of the second blade segment may be substantially parallel to, or colinear with, a longitudinal axis of the first blade segment in the nested storage arrangement.

The second blade segment preferably constitutes at least 10% of the total length of the split wind turbine blade when assembled. More preferably, the second blade segment may constitute at least 20% of the total length of the split wind turbine blade when assembled. The first blade segment preferably constitutes at least 20% or, more preferably at least 30% of the total length of the split wind turbine blade when assembled. The first blade segment preferably constitutes a greater proportion of the total length of the split wind turbine blade, when assembled, than the second blade segment.

The nested transport or storage arrangement may further comprise an inboard support structure which supports an inboard end of the first blade segment and an inboard end of the second blade segment such that the inboard ends of the first and second segments are fixed in position relative to one another. The inboard support structure may rest on a support surface which may be a ground surface or a loading surface of a transport medium. The inboard support structure may be comprised of an inner and an outer support element. Thus, a first blade segment may be supported at its inboard end in an outer inboard support element of the inboard support structure. Hence, the outer inboard support element may rest on a support surface which may be a ground surface or a loading surface of a transport medium. A second blade segment may be supported at its inboard end in an inner inboard support element of the inboard support structure.

At its outboard region, a first blade segment may be supported at a portion thereof in an outer outboard support element such as a support frame, which may form part of the nested transport or support arrangement. Hence, the outer outboard support element may rest on a support surface which may be a ground surface or a loading surface of a transport medium. A second blade segment may be supported at its outboard end in an inner outboard support element, which inner outboard support element my in particular be supported on an inside surface of an outboard region of said first blade segment.

The storage or transport arrangement preferably supports the first and second blade segments such that the segments are spaced apart, i.e. not in direct physical contact with one another. Accordingly, the second blade segment preferably does not interfere with nor directly contact the first blade segment in the nested transport arrangement.

The inboard end of the second blade segment may comprise a connection face configured for end-to-end connection with an adjacent blade segment via a bolted connection, or via other connection means. The second blade segment may be fixed to the inboard support structure via bolted connection, or other connection means, between the blade inboard connection face and the inboard support structure.

The first blade segment may comprise a blade root portion of the split wind turbine blade. The first blade segment may be fixed to the support structure via a bolted connection, or via other connection means, between the blade root face of the root portion and the inboard support structure.

Optionally, the inboard support structure may comprise a main portion and a detachable subframe portion. The subframe portion may support the inboard end of the second blade segment. The main portion may support the inboard end of the first blade segment. The subframe portion is preferably located substantially centrally relative to the main portion. The subframe portion may be bolted to the main portion or detachably fixed thereto by other fastening means.

The second blade segment preferably comprises an airfoil profile, defining a pressure side and a suction side which meet at a leading edge and a trailing edge. The airfoil portion is comprised mainly of a blade shell, structurally supported by an internal longitudinally extending structural element usually in the form of one or more shear webs, possibly a pair of shear webs, or a spar. The first blade segment preferably comprises shell having an airfoil profile defining a pressure side and a suction side, which sides meet at a leading edge and a trailing edge of the first blade segment.

The first blade segment may include an internal shear web. The second blade segment may be orientated relative to the first blade segment such that a pressure side or a suction side of the first blade segment faces the shear web of the first segment. A chordwise axis of the second blade segment may extend in a thickness direction of the first blade segment.

The other of the pressure or suction side of the second blade segment may face towards the leading edge or trailing edge of the first blade segment. Alternatively, the other of the pressure or suction side of the second blade segment may face another shear web, in other words, the second blade segment may extend longitudinally in the space between two proximate shear webs. In other words, a second blade segment may be positioned between two shear webs of the first blade segment, with the chordwise axis of the second blade segment extending in a thickness direction of the first blade segment.

The second blade segment is preferably orientated relative to the first blade segment such that a chord of the second blade segment is substantially transverse to a chord of the first blade segment. Preferably, the chordwise direction of the second blade segment extends substantially perpendicular to the chordwise direction of the first blade segment, when stored in the nested configuration. The chordwise plane of the second blade segment may thus extend substantially parallel to a shear web of the first blade segment.

The first blade segment may comprise a pair of mutually spaced shear webs. The second blade segment may be arranged in a region defined between the mutually spaced-apart shear webs.

The second blade segment may be secured within the first blade segment by means of packing material arranged between an outer surface of the second blade segment and one or more of an inner surface of the first blade segment and/or a shear web.

The packing material is preferably at least partially compressible. More preferably, the packing material may be at least partially elastically compressible. Preferably, the packing material comprises foam. Preferably the foam is an elastically compressible polymer- based foam. Optionally, advantageously, the packing material may be pre-formed. For example the packing material to be positioned between the outside surface of a second, i.e. inner, blade segment and the inside surface of a first, i.e. outer, blade segment may be pre-shaped to conform to the respective aforementioned surfaces. The packing material may in particular provide support to the inner, i.e. second, blade segment, when nested inside the outer, i.e. first, blade segment. The packing material may in particular be supported on the inside surface of the outer, i.e. first, blade segment. This packing material may optionally be provided contacting a portion of an outboard region of an inner surface of an outer, i.e. first, blade segment and contacting a portion of an outboard region of an outer surface of an inner, i.e. second, blade segment. In embodiments, packing material may optionally be provided contacting a portion of an inboard region of an inner surface of an outer, i.e. first, blade segment and contacting a portion of an inboard region of an outer surface of an inner, i.e. second, blade segment.

Preferably the packing material comprises a contoured portion that substantially matches a profile of the outer surface of the second blade segment against which it is arranged. Additionally or alternatively, the packing material may comprise a contoured portion that substantially matches a profile of the inner surface of the first blade segment against which it is arranged.

Advantageously, the inner, i.e. second, blade segment, at an outboard region thereof, may be primarily supported in the outer, i.e. first blade segment by said packing material. Advantageously, the inner, i.e. second, blade segment, at an inboard region thereof, may be primarily supported at an inboard region of the outer, i.e. first blade segment by said packing material. Advantageously, the inner, i.e. second, blade segment, along the entire length thereof, may be primarily supported in the outer, i.e. first blade segment by said packing material. In embodiments, an inner outboard support element, between said outer blade segment and an outboard region of said inner blade segment, may comprise said packing material. In embodiments, an inner inboard support element, between an inboard region of said outer blade segment and an inboard region of said inner blade segment, may comprise said packing material.

An outboard portion of the second blade segment may be supported within the first blade segment by a moveable support. The moveable support may be configured to support the second segment against an inner surface of the first segment during insertion of the second segment into the first segment. The moveable support may comprise one or more wheels or sliding elements to facilitate movement of the moveable support over or along the inner surface of the first blade segment. A sliding element may comprise a polymer sliding portion, such as a nylon skid, configured to slide against the inner surface of the first blade segment.

The second blade segment may be secured within the first blade segment by the movable support.

The split wind turbine blade may be a pre-bent blade i.e. it may exhibit a degree of bending. For example, the second blade segment may be curved between its inboard and outboard ends in the nested storage arrangement.

In a second aspect of the invention there is provided a method of arranging a split wind turbine blade for transport, wherein the split wind turbine blade comprises a plurality of longitudinally extending blade segments configured for end-to-end connection to form an assembled split wind turbine blade. The method comprises providing a first blade segment, providing a second blade segment, and arranging the second blade segment inside the first blade segment in a nested arrangement and securing the nested blade arrangement in a transport medium, and transporting said split blade in said nested configuration.

A method of transporting a split wind turbine blade per the present invention is defined in appended claim 14. Further optional features thereof are defined in subclaims 15-17. Still further optional method features are discussed in the foregoing description.

The split wind turbine blade may be a pre-bent blade and the second blade segment may be curved between its inboard and outboard ends. The method further may further comprise straightening the second blade segment by arranging the second blade segment inside the first blade segment such that the nested configuration comprises a straightened second blade segment.

The method may comprise supporting inboard ends of the first and second blade segment using a support structure, in particular a inboard support structure. An inboard support structure may comprise an outer element and an inner element. An outer element of said support structure may in particular rest on a support surface and support an outer blade segment of a nested blade arrangement. An inner element of said support structure may in particular support an inner blade segment of a nested blade arrangement. An inner element of said support structure may in particular be supported primarily or entirely on an inner surface of an outer segment of a nested blade arrangement. An inner element of said support structure may in particular be supported primarily or entirely on an outer element of said inboard support structure.

The method may comprise removably fixing an inboard end of the second blade segment to an inner inboard support element of an inboard support structure, inserting the second blade segment into the first blade segment, and removably fixing the first blade segment to the outer inboard support element of an inboard support structure such that the inboard ends of the second and first blade segments are fixed in position relative to one another.

The method may comprise removably fixing an inboard end of the second blade segment to an inner inboard support element, inserting the second blade segment into the first blade segment, and removably fixing the inboard end of the first blade segment to the inboard inner surface of the outer blade segment such that the inboard ends of the second and first blade segments are fixed in position relative to one another. In embodiments, the inner inboard support element may be partially plugged into an inner region of the inner, i.e. second, blade segment. Accordingly, the inner inboard support element may provide support to the inner, i.e. second, blade segment at an inner surface thereof. At the same time, the inner inboard support element may itself be supported on an inside surface of said outer, i.e. first, blade segment. Alternatively, the inner inboard support element may be supported on an outer inboard support element of an inboard support structure.

In embodiments, the inboard support structure may comprise a main portion and a detachable subframe portion. The main portion may be referred to as an outer portion. The detachable subframe portion may be referred to as an inner portion. The method may comprise removably fixing the second blade segment to the subframe portion, and removably fixing the first blade segment to the main portion. The method may subsequently comprise inserting the second blade segment through the main portion of the support structure and into the first blade segment. The method may comprise removably fixing the subframe portion to the main portion.

A transport arrangement according to the present disclosure may be loaded with wind turbine blade segments, secured on a transport medium and transported from a loading location to an unloading location of the blade segments. A transport medium may in particular include one or more of a road transport truck, rail transport carriages, an aircraft, or a maritime shipping vessel. A loading location may for example include a manufacturing site or transport preparation site. An unloading location may typically include a receiving area such as at a wind turbine site or a wind turbine construction site. A transport medium may typically include a road transport medium, a rail transport medium or a shipping vessel. In some cases, a transport medium may include an aircraft. A loading or unloading location for the storage arrangement may therefore include a loading or unloading zone at an aircraft takeoff or landing area. A transport medium may also include a materials handling arrangement e.g. at a manufacturing site or marshalling site such as at a shipping quayside or rail head or road transport marshalling yard. Hence, the method of the invention includes loading the nested blade transport arrangement onto a transport medium. The method of the invention may further include unloading the nested storage arrangement from a transport medium. Still further, the method of the invention may include unloading the blade segments from the nested transport arrangement. When using a road transport medium such as a truck, the nested transport arrangement may be loaded onto a truck bed drawn by a tractor. A truck bed may be extendable e.g. telescopically extendable. Alternatively, the truck may include a dolly. A dolly may be drawn behind the truck’s tractor. In embodiments, the tractive force between the truck tractor and the dolly may be primarily passed through the blade segments held in the storage arrangement. The storage arrangement may be loaded onto railcar beds and transported by rail. For shipping, a storage arrangement may be loaded with a first end and a second end on a cargo deck. For air transport, the support arrangement may be inserted through an open cargo door in the aircraft. For example, the support arrangement may be inserted longitudinally, into a cargo hold, through an open cargo door at the rear of the aircraft. Alternatively, the support arrangement may be inserted laterally or diagonally, into a cargo hold (sometimes known as a cargo bay), through an open cargo door along the side of the aircraft. Alternatively, the support arrangement may be inserted upwardly into a cargo hold from beneath an aircraft, through an open cargo door in the aircraft underbelly. Optionally, for air cargo, the support arrangement may be placed on a pallet for insertion into a cargo hold of an aircraft. Optionally, for air transport, and in order to reduce payload weight, a pallet on which the nested blade support arrangement is positioned for loading of the support arrangement may be removed after fixing the support arrangement in position in the aircraft cargo hold and before the aircraft gets airborne with the split blade. When loading a nested blade arrangement onto a transport medium, the inboard ends of the blade segments, supported in the support structure may face forwards, in the direction of travel. Alternatively, when loading a nested blade arrangement onto a transport medium, the inboard ends of the blade segments, supported in the support structure may face rearwards relative to the direction of travel. When loaded onto a transport medium, the inboard ends of the blade segments may be supported in the inboard support structure, which inboard support structure rests on a transport medium. When loaded onto a transport medium, the outboard ends of the blade nested segments may be supported in an outboard support element such as an outboard transport frame. An outboard support element may surround and secure a portion of the outboard end of the first blade segment. To this end, an outboard support element may include a releasable clamping arrangement. The outboard support element may be closed around an outboard region of the first blade segment and may be capable of being opened to allow the blade to be inserted or extracted. Alternatively, the outboard support element may be removed or applied by passing the outboard portion of the first segment in or out through the outboard support element. Preferably the inboard support structure is secured on a loading surface of the transport medium. Preferably the outboard support element may be secured on a further loading surface of the transport medium. Thus, in all cases, the weight of the blade segments may be primarily supported by the main support frames of the nested support arrangement, these including, notably, an inboard support structure and an outboard support element. Thus, a support surface on which the nested blade arrangement rests may be a transport surface such as a cargo deck or loading deck or loading surface or such like.

Brief description of Figures

Embodiments of the present invention will now be described by way of non-limiting examples only, with reference to the accompanying, not to scale figures, in which:

Figure 1 shows a schematic perspective view of a wind turbine comprising split wind turbine blades each formed of a plurality of longitudinally-extending blade segments connected end-to-end;

Figure 2 shows a schematic side view of a nested storage arrangement of a split wind turbine blade comprising a second blade segment stored upright inside a first blade segment;

Figure 3 schematically shows an end view of an inboard support structure configured to support blade segments in the nested storage arrangement;

Figures 4a and 4b show cutaway views of a nested storage arrangement showing examples of a moveable support configured to support an outboard portion of a second blade segment; Figure 5a is a schematic cross-sectional view of a nested storage arrangement wherein a first blade segment comprises a pair of shear webs and a second blade segment is arranged in a region between the shear webs;

Figure 5b is a schematic cross-sectional plan view of a nested storage arrangement comprising a second blade segment arranged between a pair of shear webs;

Figure 6 shows a schematic view of an example of an inboard support structure according to one embodiment, comprising a main portion and a detachable subframe portion; and

Figures 7a to 7c show side and end views of an arrangement of a split wind turbine blade in a nested storage arrangement comprising an inboard support structure according to one embodiment;

Figs. 8a and 8b show alternative exemplary embodiments of an inboard support structure according to further optional aspects of the invention;

Fig. 9 shows a side view of still further alternative embodiments of a nested storage or transport arrangement for split blades;

Fig. 10 shows an exemplary embodiment for transporting nested split blades in an aircraft;

Figs. 11a and 11b illustrate optional additional details for facilitating loading and unloading a nested split blade arrangement into or out from an aircraft cargo bay;

Fig. 12 shows a possible arrangement for transporting nested split blades on a rail transport medium;

Fig. 13 shows a possible arrangement for transporting nested split blades on a road transport medium;

Fig. 14 shows a possible arrangement for transporting nested split blades on a maritime vessel cargo bay.

Detailed description

Figure 1 is a schematic perspective view of a modern utility-scale wind turbine 10. The wind turbine 10 comprises a tower 12 supporting a nacelle 14 to which a rotor 16 is mounted. The rotor 16 comprises a plurality of radially extending split wind turbine blades 18 which are attached at their respective root ends 20 to a central hub 22. A horizontal wind turbine blade has a pressure side 18b and a suction side 18a

The split wind turbine blades 18 each comprise a first longitudinally extending blade segment 24b and a second longitudinally-extending blade segment 24a. As shown in Figure 1 , the second blade segment 24a may be an outboard segment. Further, the second blade segment 24a may comprise a tip 26 of the split wind turbine blade 18. The first blade segment 24b may be an inboard blade segment as shown in Figure 1 . The terms “inboard” and “outboard” describe the relative proximity of each blade segment 24b, 24a to the rotor hub 22. The first blade segment 24b may comprise the root 20 of the split wind turbine blade 18 at which the blade is attached to the central rotor hub 22. Preferably, the first and second blade segments 24b, 24a may comprise a composite material shell, formed of a material such as glass fibre reinforced plastic (GFRP).

The first and second blade segments 24b, 24a are configured for end-to end connection to form the split wind turbine blade 18. As such, an inboard end 28a of the second blade segment 24a may comprise a connection face 30a configured for connection to an adjacent blade segment. Accordingly, an outboard end 32b of the first blade segment 24b may comprise a connection face 30b configured for connection to the second blade segment 24a. Preferably, the connection faces 30a and 30b abut as shown in Figure 1 when the first and second blade segments 24a, 24b are connected end-to-end to form the split wind turbine blade 18. An abutment between first and second blade segments 24b, 24a may be along abutment faces which could run perpendicular to a blade’s chordwise and spanwise directions. Alternatively, an abutment between first and second blade segments 24b, 24a may be along abutment faces which could run at an oblique angle to a blade’s chordwise and spanwise directions, for example, in a scarf type joint. Other types of interface at an abutment region between blade segments may also be envisaged.

Providing the wind turbine blade 18 as a plurality of blade segments 24b, 24a facilitates easier transportation of the large components to a wind turbine site prior to assembly with the central hub 22 and other components of the wind turbine 18. In accordance with examples of the present invention, the blade segments 24a, 24b of each split wind turbine blade 18 may be stored and/or transported in an advantageous nested storage arrangement as will now be described with reference to the remaining figures.

Figure 2 shows a nested storage arrangement 34 of a split wind turbine blade 18. The first blade segment 24b is preferably substantially hollow. The second blade segment 24a (shown in dashed lines in Figure 2) is stored inside the first blade segment 24b in the nested storage arrangement 34. As such, the total space required during storage and transportation of the split wind turbine blade 18 is significantly reduced in comparison to storing and transporting blade segments 24a, 24b separately, and the nested storage arrangement 34 facilitates storage and transportation of the split wind turbine blade 18 as a single, sub-assembled item.

According to the invention, a nested storage or transport arrangement 34 of a split wind turbine blade 18 of a horizontal axis wind turbine is provided. The blade 18 has an aerodynamic pressure side 18a and an aerodynamic suction side 18b extending between a blade root end 20 and a blade tip end 26. The split wind turbine blade 18 comprises a plurality of longitudinally extending blade segments configured for end-to- end connection to form the split wind turbine blade 18. The blade segments include a first blade segment 24b and a second blade segment 24a, wherein a second blade segment 24a is stored inside a first blade segment 24b. The nested storage arrangement 34 further comprises an inboard support structure 36 including an outer inboard support element 36b which supports an inboard end 28b of a first blade segment 24b on a support surface and an inner inboard support element 36a which supports an inboard end 28a of a second blade segment 24a at said inboard end 28b of the first blade segment 24b such that the inboard ends 28b, 28a of respective first and second segments 24b, 24a are fixed in position relative to one another.

In the nested storage arrangement 34, the second blade segment 24a is protected within the first blade segment 24b. This is particularly advantageous in examples where the second blade segment 24a comprises the tip 26 of the split wind turbine blade 18. The tip 26, or tip portion, of the wind turbine blade 18 is typically the most fragile portion of the wind turbine blade 18 which can be susceptible to damage during transport or storage. Damage to the tip portion 26 has a significant detrimental impact on the aerodynamic performance of the blade 18. Any such damage must therefore be remedied on-site prior to assembling the blade 18 with the wind turbine 10. By protecting the tip 26 of the blade 18 inside a first blade segment 24b during storage and transit, the risk of damage requiring additional on-site work is reduced or eliminated entirely. As such, the nested storage arrangement 34 facilitates a faster and more efficient blade assembly process.

The first blade segment 24b preferably constitutes a greater proportion of the total length of the split wind turbine blade 18 than the second blade segment 24a. This enables storage of substantially the whole second blade segment 24a inside the first blade segment 24b. In this example, the second blade segment 24a constitutes around 30% of the total length of the split wind turbine blade 18 and the entire second blade segment 24a fits inside the first blade segment 24b.

Referring still to Figure 2, the nested storage arrangement 34 may additionally comprise an inboard support structure 36 as well as an outboard support structure. The inboard support structure 36 may support respective inboard ends 28a, 28b of both the first blade segment 24b and the second blade segment 24a when the split wind turbine blade 18 is arranged in the nested storage arrangement 34. Preferably, the first and second blade segments 24b, 24a do not directly contact one another in the nested storage arrangement 34. The inboard ends 28a, 28b of each blade segment 24a, 24b are therefore preferably releasably fixed in position. Optionally, the inboard support structure 36 may comprise an inner inboard support element 36a and an outer inboard support element, which elements 36a, 36b are mutually directly fixed to each other as shown for example in Fig. 3. Optionally, the inboard support structure 36 may comprise an inner inboard support element 36a and an outer inboard support element, which elements 36a, 36b are mutually directly, detachably fixed to each other as shown for example in Fig. 6 or in Figs 7a-c. As such, the inboard ends 28a, 28b of the blade segments 24a, 24b may be fixed in position relative to one another thereby to constitute an inboard support structure 36. This helps to ensure that the blade segments 24a, 24b are, and remain, spaced apart during storage and/or transportation. This configuration of the nested storage arrangement 34 therefore further helps to protect the second blade segment 24a. An outboard support structure may comprise an outboard support element in the form of an outer outboard support element 45. This may support a portion of an outboard region 32b of a first blade segment 24b. The outer outboard support element may be a frame or cradle. It may in particular rest on a support surface. An outboard support structure may further include an inner outboard support element 67. This inner element 67 may in particular support an outboard region 32a of said second blade segment 24a at an inside surface of a first blade segment 24b. The inner outboard support element 67 may comprise packing material 62 whether supple or pre-shaped. In particular, the outboard end region 32a of a second blade segment 24a may be secured within the first blade segment 24b by means of packing material 62 arranged between an outer surface of the second blade segment 24a and one or more of an inner surface of the first blade segment 24b and/or a shear web 60. In this embodiment, the inner outboard support element 67 may comprise packing material 62 arranged between an outer surface of the second blade segment 24a and one or more of an inner surface of the first blade segment 24b and/or a shear web (60). In embodiments, the inner outboard support element 67 may comprise a mobile element, 44 described hereinbelow.

With reference now also to Figure 3, which shows an end view of the nested storage arrangement 34, the second blade segment 24a may be releasably fixed to the support structure 36 via a bolted connection 38. In particularly advantageous examples, the connection face 30a of the second blade segment 24a may be configured for a bolted end- to-end connection with an adjacent blade segment to form the assembled split wind turbine blade 18. In such an example, the same connection means 38 configured for connecting the blade segments 24a, 24b may be used to releasably fix the second blade segment 24a to the support structure 36. As such, in the nested storage arrangement 34, the second blade segment 24a may be fixed to the support structure 36 via a bolted connection 38 between its connection face 30a and the support structure 36 without requiring additional tooling or fixturing.

In this example, the first blade segment 24b comprises the root 20 of the blade 18 at its inboard end 28b. The inboard end 28b of the first blade segment 24b may be releasably fixed to the support structure 36 via root connection means 40 configured for connecting the split wind turbine blade 18 to the central hub 22 of the rotor 16 when assembled. The root connection means 40 preferably comprises a bolted connection. Fixing the first blade segment 24b to the support structure 36 may therefore advantageously not require any additional tooling or fixturing beyond that already required for connecting the split blade 18 to the central hub 22.

In some examples, the first and second blade segments 24b, 24a may be arranged in the nested storage arrangement 34 by first supporting the inboard end 28a of the second blade segment 24a on the support structure 36, and then arranging the first blade segment 24b over the second blade segment 24a. For example, the second blade segment 24a may be attached to the support structure 36 in a cantilevered arrangement before being inserted into the first blade segment 24b. Alternatively, the first blade segment 24b may instead be sheathed over the second blade segment 24a. After arranging the second blade segment 24a inside the first blade segment 24b, the inboard end 28b of the first blade segment 24b may then be supported on the support structure 36, for example via a bolted connection 40.

An outboard portion 32a of the second blade segment 24a may be supported within the first blade segment 24b by a moveable support 44 as shown most clearly in the cutaway views of Figures 4a and 4b. The moveable support 44 is preferably configured to support the second blade segment 24a against an inner surface 46 of the first blade segment 24b during arrangement of the blade segment in a nested arrangement 34. The moveable support 44 is preferably attached to, and moves with, the second blade segment 24a during arrangement of the blade segments. In particular, the moveable support 44 preferably facilitates movement of the second blade segment 24a along the inner surface 46 of the first blade segment 24b whilst protecting the second blade segment 24a from directly contacting the first blade segment 24b.

The moveable support 44 facilitates easier and faster arrangement of the first and first blade segments 24b, 24a in the nested storage arrangement 34. In some examples, as shown in Figure 4a, the moveable support 44 may comprise one or more wheels 48 which move along the inner surface 46 of the first blade segment 24b whilst the outboard portion 32a of the second blade segment 24a is supported and protected. In other examples, the moveable support 44 may instead comprise a sliding element 50 configured to slide over the inner surface 46 of the first blade segment 24b, as shown in Figure 4b. The sliding element 50 may comprise a polymer skid configured to slide against the inner surface 46 of the first blade segment 24b without causing damage to the inner surface 46.

Optionally therefore, the nested storage arrangement 34 may further comprise a moveable support 44 receiving and supporting a portion of an outboard region 32a of the second blade segment 24a. The moveable support 44 is preferably configured to contact and move over an inner surface 46 of a said first blade segment 24b during insertion of the second blade segment 24a into a first blade segment 24b. The moveable support 44 may comprise one or more wheels 48 or sliding elements 50 to facilitate movement of the moveable support 44 over or along the inner surface 46 of the first blade segment 24b. Advantageously, a movable support 44 may be configured to rest against one or more of an inner surface 46 of the first blade segment 24b and/or a shear web 60 when a second blade segment 24b is received, i.e. fully inserted, inside a first blade segment 24b. This may thereby secure the inner, i.e. second, blade segment 24a against lateral movement relative to the blade longitudinal extension direction. In other words, the second blade segment 24a may be secured against lateral movement within a first blade segment 24b. A movable support 44 may furthermore be configured as, and perform the function of, an inner outboard support element 67.

Figures 5a and 5b show section views along lines A-A and B-B in Figure 2 respectively. The split wind turbine blade 18 preferably comprises an airfoil profile configured to generate lift from wind incident on the blade 18 in use. As shown most clearly in Figure 5a, the first and second blade segments 24b, 24a may therefore each comprise an airfoil profile. As such, the second blade segment 24a preferably comprises a windward side 52a and a leeward side 54a which meet at a leading edge 56a and at a trailing edge 58a of the second blade segment 24a. Similarly, the first blade segment 24b may comprise a windward side 52b and a leeward side 54b which meet at a leading edge 56b and at a trailing edge 58b of the first blade segment 24b.

Optionally therefore, the first blade segment 24b may comprise a shear web 60 and the second blade segment 24a may be orientated relative to the first blade segment 24b such that a pressure side 18a, 52a or a suction side 18b, 54a of the second blade segment 24a faces the shear web 60. Alternatively, the first blade segment 24b may comprise a pair of mutually spaced shear webs 60, and the second blade segment 24a may be arranged in a region 66 defined between the mutually spaced shear webs 60.

In some examples, the first blade segment 24b may comprise one or more shear webs 60. For example, as shown in Figures 5a and 5b, the first blade segment 24b may comprise a pair of mutually spaced shear webs 60. The shear webs 60 are preferably attached between the windward and leeward sides 52b, 54b of the first blade segment 24b to take up shear loads experienced by the split wind turbine blade 18 in use.

In examples where the first blade segment 24b comprises one or more shear webs 60, the second blade segment 24a is preferably orientated relative to the first blade segment 24b such that one of the windward or leeward sides 52a, 54a of the second blade segment 24a faces the shear web 60 in the nested storage arrangement 34. Such a relative orientation of the second and first blade segments 24a, 24b helps to ensure that the blade segments stay spaced apart during storage and/or transport in the nested storage arrangement 34, further minimising direct contact between the respective segments 24a, 24b despite the presence of one or more shear webs 60 in the first blade segment 24b.

In some preferred examples, the second blade segment 24a may be secured within the first blade segment 24b by packing material 62. The packing material 62 is preferably arranged between an outer surface 64 of the second blade segment 24a and an inner surface 46 of a shear web 60 of the first blade segment 24b. The packing material 62 restricts movement of the second blade segment 24a relative to the first blade segment 24b in the nested storage arrangement 34. In advantageous examples, the packing material 62 restricts movement of the second blade segment 24a in all directions within the first blade segment 24b to effectively limit any potential oscillations or vibrations of the second blade segment 24a.

In examples such as that shown in Figures 5a and 5b, wherein the first blade segment 24b comprises a pair of mutually spaced shear webs 60, the second blade segment 24a is preferably arranged in a region 66 defined between the mutually spaced shear webs 60. In such a configuration of a nested storage arrangement 34, the second blade segment 24a may be secured within the first blade segment 24b by packing material 62 arranged between the outer surface 64 of the second blade segment 24a and each shear web 60.

The packing material 62 is preferably at least partially compressible such that it may be at least partially compressed between a second blade segment 24a and each shear web 60 in the nested storage arrangement 34. In some examples, the packing material 62 may be at least partially elastically compressible. In such an example, the packing material 62 may advantageously exert a force on both the second blade segment 24a and the shear webs 60 to secure the second blade segment 24a in position relative to the first blade segment 24b.

As shown in Figure 5a, in some examples the packing material 62 may comprise a contoured portion 68 that matches the profile of the outer surface 64 of the second blade segment 24a. Such a contoured portion 68 helps to distribute pressure evenly on the surface 64 of the second blade segment 24a and helps to ensure that the packing material 62 is securely wedged between the second blade segment 24a and the shear webs 60.

In some examples, the moveable support 44 may be configured to help secure the second blade segment 24a inside the first blade segment 24b. For example, and as shown in Figure 5b, the moveable support 44 may be configured to become wedged between the pair of mutually spaced shear webs 60 when the second blade segment 24a is arranged in the region 66 defined between the shear webs 60. As such, the moveable support 44 may help to restrict movement of the second blade segment 24a within the first blade segment 24b following arrangement of the segments in the nested storage arrangement 34.

The split wind turbine blade 18 may be a pre-bent blade. A pre-bent blade 18 advantageously reduces the risk of the blade 18 striking the tower 12 of the wind turbine 10 in use during adverse weather conditions because the tip 26 of the blade 18 is curved away from the tower 12. As such, the second blade segment 24a may be curved between its inboard and outboard ends 28a, 32a. As shown in Figure 5b, in examples where the second blade segment 24a is curved, the curved second blade segment 24a may be caused to straighten upon insertion inside the first blade segment 24b when arranging the segments in the nested storage arrangement 34. In such an example, the use of packing material 62 and/or a moveable support 44 is particularly advantageous to protect the first and first blade segments 24a, 24b during straightening and insertion of the second blade segment 24a. In other examples, a curved second blade segment 24a may be straightened prior to insertion into the first blade segment 24b. As such, the nested storage arrangement 34 may comprise a straightened second blade segment 24a.

Figure 6 shows an example of an inboard support structure 36 comprising an outer portion 36b, which may be seen as a main portion 70, and an inner portion 36a which may be seen as a subframe portion 72, in particular a detachable subframe portion 72. The inboard support structure 36 is shown in Figure 6 in a detached I disassembled configuration. Preferably, a detachable subframe portion 72 may be located substantially centrally relative to a main portion 70, i.e. preferably a substantially central portion of the inboard support structure 36 is detachable. As such, in this example, the main portion 70 is an outer portion 36b of the inboard support structure 36, and the detachable subframe portion 72 is an inner portion 36a of the inboard support structure 36.

As shown in Figure 7a, the subframe (inner) portion 72 supports the inboard end 28a of the second blade segment 24a. The inboard end 28a of the second blade segment 24a may be releasably fixed to the subframe portion 72, for example by means of a bolted connection 38.

The inboard end 28b of the first blade segment 24b is preferably supported by the main (outer) portion 70 of the inboard support structure 36, as shown in Figure 7b. The inboard end 28b of the first blade segment 24b may be releasably fixed to the main portion 70 of the inboard support structure 36, for example by means of a bolted connection 40.

With reference now to Figure 7c, a subframe portion 72 of the inboard support structure 36 may be releasably connected to a main portion 70 of the inboard support structure 36. For example, the subframe portion 72 may be connected to the main portion 70 via a bolted connection (not shown).

Optionally therefore, an inboard support structure 36 configured with a detachable subframe portion 72 advantageously facilitates an alternative method of arranging the second blade segment 24a inside the first blade segment 24b. For example, the second blade segment 24a may be releasably fixed to the subframe portion 72, and the first blade segment 24b may be releasably fixed to the main portion 70 of the inboard support structure 36 as shown in Figures 7a and 7b. The second blade segment 24a, attached to the subframe portion 72, may then be inserted through the main portion 70 of the inboard support structure 36 and into the first blade segment 24b. Subsequently, the subframe portion 72 may then be releasably connected to the main portion 70 of the inboard support structure 36.

Therefore, optionally, a first blade segment 24b may be fixed to an outer inboard support element 36b of the inboard support structure 36 via a bolted connection between a blade root face 20a of the first blade segment 24a and the outer inboard support element 36b. Moreover, the inboard end 28a of a second blade segment 24a may comprise a connection face 30a configured for end-to-end connection with an adjacent blade segment at a connection interface, and a second blade segment 24a may be fixed to the inner inboard support element 36a via a bolted or other matching e.g. scarfed or interleaved connection between its connection face 30a and the inner inboard support element 36a of said inboard support structure 36.

Optionally the inner inboard support element 36a and the outer inboard support element 36b of an inboard support structure 36 may comprise respectively a main portion 70 and a subframe portion 72 of said inboard support structure 36; and the subframe portion 72 may be supportingly fixed to and detachable from said main portion 70. The subframe portion 72 may supports the inboard end 28a of a second blade segment 24a, and the main portion 70 may support the inboard end 28b of a first blade segment 24b.

Such a configuration and method may be advantageous because it requires fewer connections or fixings to be made whilst the first and first blade segments 24a, 24b are being arranged together. For example, the main connections between the blade segments 24a, 24b and the respective portions 70, 72 of the support structure 36 can be made separately. Only a few simple connections between the subframe portion 72 and the main portion 70 are then required to support the blade shells 24a, 24b relative to one another following the arrangement of the second blade segment 24a inside the first blade segment 24b. As such, the process of arranging the second blade segment 24a inside the first blade segment 24b in the nested storage arrangement 34 may be simplified in examples where the support structure 36 comprises a detachable subframe portion 72. The nested storage arrangement 34 and methods for arranging the split blade 18 in the nested storage arrangement 34 advantageously facilitate more efficient storage and transport of a split wind turbine blade 18.

In some examples, the split wind turbine blade 18 may comprise a second blade segment 24a, a first blade segment 24b, and one or more additional blade segments. In some examples, one or more of the first and/or first blade segments 24a, 24b may not comprise either of the root 20 or tip 26 of the split wind turbine blade 18. As such, the first and/or first blade segments 24a, 24b may be intermediate blade segments configured for connection end-to-end between blade segments comprising the root end 20 and tip end 26 of the blade. Preferably the inboard ends 28a, 28b of the blade segments 24a, 24b in such examples are supported on a support structure 36 in the same manner as previously described.

The nested storage arrangement 34 in some examples may comprise first and first blade segments 24a, 24b and one or more additional blade segments. As such, the nested storage arrangement 34 may comprise a plurality of blade segments stored inside the first blade segment 24b. The nested storage arrangement 34 may comprise blade segments configured in a “Russian dolls” arrangement. Preferably the first blade segment 24b is the most inboard blade segment of the split wind turbine blade 18.

In some examples wherein the split wind turbine blade 18 is a pre-bent blade, and the second blade segment 24a is curved between its inboard and outboard ends 28a, 32a, the curved second blade segment 24a may be stored inside the first blade segment 24b in its curved I pre-bent form. For example, if the first blade segment 24b does not comprise one or more shear webs 60, the curved second blade segment 24a may be stored inside the first blade segment 24b in the nested storage arrangement 34 in a curved I pre-bent form without being straightened. Thus, the split wind turbine blade 18 may be a pre-bent blade, and a second blade segment 24a may thereby be curved between its inboard and outboard ends 28a, 32a when inserted within the outer, i.e. first, blade segment 24b.

In some examples, the first blade segment 24b may comprise spar caps (not shown) associated with the windward and leeward sides 52b, 54b of the first blade segment 24b. The first blade segment 24b may therefore comprise a spar structure formed of individual shear webs 60 extending between opposing spar caps. Alternatively, the first blade segment 24b may comprise a box spar structure wherein leading edge and trailing edge sides of the box spar act as shear webs, and windward and leeward sides of the box spar act as spar caps. In the context of the present invention, it will be understood that the leading and trailing edge sides of a box spar structure are substantially synonymous with the shear webs 60 described above. Any reference herein to shear webs 60 will therefore be understood to refer equally to sides of a box spar structure.

In examples where the first blade segment 24b does not comprise one or more shear webs 60, the second blade segment 24a is preferably secured within the first blade segment 24b by packing material 62 arranged between an outer surface 64 of the second blade segment 24b and an inner surface 46 of the first blade segment 24b. The packing material 62 in such an example serves the same purpose as previously described, namely to restrict movement of the second blade segment 24a relative to the first blade segment 24b. The packing material 62 in such an example preferably comprises a contoured portion that substantially matches the profile of the inner surface 46 of the first blade segment 24b.

In similar examples where the first blade segment 24b does not comprise one or more shear webs 60, the moveable support 44 may be configured in such a way that it becomes wedged between the outer surface 64 of the second blade segment 24b and the inner surface 46 of the first blade segment 24b when the second blade segment 24a is arranged inside the first blade segment 24b in the nested storage arrangement 34. In such examples the moveable support 44 may therefore help to restrict movement of the second blade segment 24a within the first blade segment 24b following arrangement of the segments in the nested storage arrangement 34.

Optionally, the nested storage or transport arrangement 34 may be configured such that an inner inboard support element 36a of an inboard support structure 36 supportingly engages an outer surface of an inboard end 28a of a second blade segment 24a. This may be achieved with reference to Figs. 6 or 7a-7c in that a subframe portion 72 of an inboard support structure 36 may include support elements contacting the outer surfaces of the second blade segment 24a. Alternatively, as shown in Figs. 8a, an inner inboard support element 36a may be provided in between an inner surface of an outer, i.e. first, blade segment 24b and an outer surface of an inner, i.e. second, blade segment 24a. In this arrangement, the loads exerted by the inboard end 28a of the inner, i.e. second, blade segment 24a may be primarily or wholly supported by the inner inboard support element 36a which may itself be primarily or wholly supported on one or more inner surfaces of an inboard region of an outer, i.e. first, blade segment 24b. In this example, an inner inboard support element of an inboard support structure 36 may be made from preformed packing material. A foam rigid or semi rigid, resilient foam material may be suitable for a pre-formed inner inboard support element which is positioned between inboard regions of a first blade segment 24b and a second blade segment 24a. Thus, an inner inboard support element 36a of a said inboard support structure 36 may also supportingly engage an inner surface of an inboard end 28b of a first blade segment 24b.

Still further, alternatively or additionally, an inner inboard support element 36a of an inboard support structure 36 may supportingly engage an inner surface of an inboard end 28a of a second blade segment 24a. Thus, as illustrated in Figs. 8a and 9, an inner inboard support element may be inserted partially inside the interior of an inner, i.e. second, blade segment 24a. As such, an inner inboard support element 36a of a said inboard support structure 36 may supportingly engage both an inner surface of an inboard end 28b of a first blade segment 24b and an inner surface of an inboard end of the second blade segment 24a. Still further, for improved stability, the inner inboard support element 36a of an inboard support structure 36 may engage both the inner and outer surfaces of the inner, i.e. second, blade segment 24a. The use of a plug-in portion of an inner inboard support element 36a into the interior of a second blade segment 24a of an inboard support structure 36 further improves the convenience of the arrangement in use, because the inner inboard support element 36a can be pre-fitted to a second blade segment 24a prior to insertion of the second blade segment 24a into the first blade segment 24b.

The first blade segment 24b may be supported in an inboard support element 36b of an inboard support frame 36 and in an outboard support frame 45, both of which may rest on a support surface. Meanwhile, the second blade segment 24a may be supported in the first blade segment 24b by means of inner support elements 36a, 67. The second blade segment 24a may in particular comprise support elements 36a, 67, pre-shaped and configured to supportingly engage a respective portion of the surface of the second blade segment 24a. At the same time, a pre-shaped support element 36a, 67 would be shaped and configured to supportingly engage an inside surface of a first blade segment 24b.

In use, the inboard support structure 36 and the outboard support frame 45 rest on a support surface which support surface may be a ground surface or a loading surface of a transport medium. Optionally, a loading surface is comprised in a shipping vessel 86 or a railcar 82 or a road haulage truck 80 or an aircraft 84 (see Figs. 10-14). The invention also provides a method of transporting a split wind turbine blade 18, wherein the split wind turbine blade 18 comprises a plurality of longitudinally extending blade segments configured for end-to-end connection to form an assembled split wind turbine blade 18, and wherein the method comprises providing a first blade segment 24b; providing a second blade segment 24a; and arranging the second blade segment 24a inside the first blade segment 24b in a nested storage arrangement thereof 34. The method further includes securing the nested blade storage arrangement 34 in a transport medium, and transporting the split blade 18 in a nested configuration thereof.

Optionally, the method may include securing an inboard support structure 36 and an outboard support element 45 of the nested support arrangement on a loading surface of a transport medium, thereby supporting said split wind turbine blade 18 in its nested configuration by said inboard support structure 36 and said outboard support element 45 on said transport loading surface.

Optionally, the split wind turbine blade 18 may be a pre-bent blade and the second blade segment 24a may be curved between its inboard and outboard ends 28a, 32a. The method may thereby further comprise straightening the second blade segment 24a by arranging the second blade segment 24a inside the first blade segment 24b such that the nested configuration comprises a straightened second blade segment 24a.

The transport medium may be selected from the group including a road transport truck 80; rail transport carriages 82; an aircraft 84; or a shipping vessel 86 (see Figs. 10-14).

With reference to Fig. 10, a nested blade arrangement 34 may be transferred to the cargo bay of an aircraft 84 via a loading door, which may by way of example be in the rear (as shown) or at the front or sides of the aircraft 84. The blade tip 26 may point forwards or rearwards in relation to the direction of travel, in accordance with preferred arrangements or perhaps in accordance with the size or shape of the cargo bay. The aircraft may include cargo holders 122 in the form of restrainers, in fixed relation to the interior of the aircraft. A holder 122 may be applied to one or both of the inboard and outboard outer support elements 45, 36b of the arrangement 34, to stabilise and secure the nested blade arrangement 34 in the aircraft. Alternatively or additionally, a holder 122 may equally well be attached directly to the first blade segment 24b. To aid transfer of the nested blade arrangement 34 into an aircraft cargo hold, there may be provided sliding aids 124 at the nested blade arrangement 34 (see Figs. 11a and 11b). These may for example be provided at the respective inboard and outboard outer support elements 36b, 45. These may aid insertion of the nested blade arrangement 34 by allowing the arrangement to glide across the aircraft’s cargo deck, for example while being lifted and/or pushed only from one end. A sliding aid 124 may for example take the form of a caster (Fig. 11a) or a skid (Fig. 11 b) and may be fixed directly to one or both the inboard and outboard outer support elements 36b, 45. In a further alternative, a pallet 126 may be provided in between a nested blade arrangement 34 and a cargo deck. In this case, the pallet 126 may be considered as a transport surface or support surface. The use of a pallet 126 may ease loading and unloading and may shorten the time needed therefor. Optionally, a sliding aid 124 may be attached to the pallet 126 (Fig. 11 b).

Considerably space savings are achievable on alternative transport modes such as railcars 82 (Fig. 12) or road transport trucks 80 (Fig. 13). In the case of marine vessels 86 (Fig. 14), a significantly larger number of wind turbine blades 18 may be transported in a single trip. In each case, the nested blade storage arrangement 34 is placed on a transport surface and secured in position for transportation.

It will be appreciated that features described in relation to the various examples above may be readily combined with features described with reference to different examples without departing from the scope of the invention as defined in the appended claims. For example, references to a transport arrangement may be understood as references to a storage arrangement and vice-versa. References herein to a segment or blade segment or blade segment are references to a longitudinally - or spanwise - extending blade segment. References to a blade segment may sometimes otherwise be known or referred to as a blade module. References to a split blade are sometimes otherwise known as a segmented blade or modular blade. References to a split blade herein are to be understood as references to a blade which can be physically divided into discrete longitudinal segments. In other words, references to a split blade are references to a fully assembled split blade, unless stated otherwise, e.g. by reference to a segment of a split blade or to a disassembled split blade. References to a blade in the present context are references to a wind turbine blade, notably to a wind turbine blade of a horizontal axis wind turbine. References to a split wind turbine blade in its assembled state are references to the blade in its fully assembled state. A split type wind turbine blade comprising two or three or more longitudinal segments may be in a state in which it is disassembled into its constituent segments, or it may be in a fully assembled state, or it may be in a partially assembled state which is to say that at least two of its segments but not all its segments are assembled together. A transport medium may otherwise be known as a transport mode, or mode of transport. Further, it will be appreciated that the above description and accompanying figures are provided merely as an example. Many alternatives to the specific split blade and method described above are therefore possible without departing from the scope of the invention as defined in the appended claims.

Claims

1. A nested storage arrangement (34) of a split wind turbine blade (18) of a horizontal axis wind turbine, the blade (18) having an aerodynamic pressure side (18a) and an aerodynamic suction side (18b) extending between a blade root end (20) and a blade tip end (26); the split wind turbine blade (18) comprising a plurality of longitudinally extending blade segments configured for end-to-end connection to form the split wind turbine blade (18), said blade segments including a first blade segment (24b) and a second blade segment (24a); wherein said second blade segment (24a) is stored inside said first blade segment (24b), and wherein said nested storage arrangement (34) further comprises an inboard support structure (36) including an outer inboard support element (36b) which supports an inboard end (28b) of said first blade segment (24b) on a support surface and an inner inboard support element (36a) which supports an inboard end (28a) of said second blade segment (24a) at said inboard end (28b) of said first blade segment (24b) such that the inboard ends (28b, 28a) of respective first and second segments (24b, 24a) are fixed in position relative to one another.

2. The nested storage arrangement (34) of claim 1 , wherein the first blade segment (24b) comprises a shear web (60) and wherein the second blade segment (24a) is orientated relative to the first blade segment (24b) such that a pressure side (18a, 52a) or a suction side (18b, 54a) of the second blade segment (24a) faces the shear web (60).

3. The nested storage arrangement (34) of any preceding claim, wherein the first blade segment (24b) comprises a pair of mutually spaced shear webs (60), and wherein the second blade segment (24a) is arranged in a region (66) defined between the mutually spaced shear webs (60).

4. The storage arrangement of claim 1 , further comprising an outer outboard support element (45) supporting a portion of an outboard region (32b) of said first blade segment (24b) on a support surface, and an inner outboard support element (67) supporting an outboard region (32a) of said second blade segment (24a) at an inside surface of said first blade segment (24b).

5. The nested storage arrangement (34) of claim 4, wherein the outboard end region (32a) of said second blade segment (24a) is secured within the first blade segment (24b) by means of packing material (62) arranged between an outer surface of the second

27 blade segment (24a) and one or more of an inner surface of the first blade segment (24b) and/or a shear web (60). [in this embodiment, the inner outboard support element 67 may comprise packing material (62) arranged between an outer surface of the second blade segment (24a) and one or more of an inner surface of the first blade segment (24b) and/or a shear web (60)]

6. The nested storage arrangement (34) of any preceding claim, said arrangement further comprising a moveable support (44) receiving and supporting a portion of an outboard region (32a) of the second blade segment (24a), said moveable support (44) being configured to contact and move over an inner surface (46) of a said first blade segment (24b) during insertion of the second blade segment (24a) into a said first blade segment (24b).

7. The nested storage arrangement (34) of Claim 6, wherein said movable support (44) is configured to rest against one or more of an inner surface (46) of the first blade segment (24b) and/or a shear web (60) when said second blade segment (24b) is received inside said first blade segment (24b) thereby securing said second blade segment (24a) within said first blade segment (24b).

8. The nested storage arrangement (34) of any preceding claim, wherein said inner inboard support element (36a) of said inboard support structure (36) supportingly engages an outer surface of an inboard end (28a) of said second blade segment (24a).

9. The nested storage arrangement (34) of any preceding claim, wherein said inner inboard support element (36a) of said inboard support structure (36) supportingly engages an inner surface of an inboard end (28a) of said second blade segment (24a).

10. The nested storage arrangement (34) of any preceding claim, wherein said inner inboard support element (36a) of said inboard support structure (36) supportingly engages an inner surface of an inboard end (28b) of said first blade segment (24b).

11. The nested storage arrangement (34) of any preceding claim, wherein said first blade segment (24b) comprises a blade root portion (20) of the split wind turbine blade (18) having a root face (20a), and wherein the first blade segment (24b) is fixed to an outer inboard support element (36b) of said inboard support structure (36) via a bolted connection between said blade root face (20a) and the outer inboard support element (36b).

12. The nested storage arrangement (34) of any claim 10 and/or 11, wherein the inner inboard support element (36a) and the outer inboard support element (36b) of said inboard support structure (36) comprise respectively a main portion (70) and a subframe portion (72) of said inboard support structure 36; wherein said subframe portion (72) is supportingly fixed to and detachable from said main portion (70), and wherein the subframe portion (72) supports the inboard end (28a) of a second blade segment (24a) and the main portion (70) supports the inboard end (28b) of the first blade segment (24b).

13. The nested storage arrangement (34) of any preceding claim, wherein the inboard support structure (36) rests on a support surface which support surface is a ground surface or a loading surface of a transport medium; optionally wherein said loading surface is comprised in a shipping vessel (86) or a railcar (82) or a road haulage truck (80) or an aircraft (84).

14. A method of transporting a split wind turbine blade (18), wherein the split wind turbine blade (18) comprises a plurality of longitudinally extending blade segments configured for end-to-end connection to form an assembled split wind turbine blade (18), and wherein the method comprises providing a first blade segment (24b); providing a second blade segment (24a); and arranging the second blade segment (24a) inside the first blade segment (24b) in a nested storage arrangement thereof (34) according to any preceding claim; and securing said nested blade storage arrangement (34) in a transport medium, and transporting said split blade (18) in a nested configuration thereof.

15. The method according to claim 14, said method including securing said support structure (36) on a loading surface of said transport medium, and placing an outboard support element (45) of said nested storage arrangement (34) on a loading surface of said transport medium, thereby supporting said split wind turbine blade (18) in its nested configuration by said support structure (36) and said outboard support element (45).

16. The method of Claim 14, wherein the split wind turbine blade (18) is a pre-bent blade and the second blade segment (24a) is curved between its inboard and outboard ends (28a, 32a), the method further comprising straightening the second blade segment (24a) by arranging the second blade segment (24a) inside the first blade segment (24b) such that the nested configuration comprises a straightened second blade segment (24a).

17. The method of any claim 14 to 16, wherein said transport medium is selected from the group including a road transport truck (80); rail transport carriages (82); an aircraft (84); or a shipping vessel (86).