De-icing system for a wind turbine blade

Abstract

A wind turbine blade having a blade de-icing system is disclosed. The blade de-icing system comprises a first channel extending longitudinally from a first location to a second location, wherein the second location is between the tip end and the first location, and a heating channel extending longitudinally from the second location to the first location along a leading edge of the wind turbine blade, the heating channel and the first channel being in fluid connection. The blade de-icing system is arranged to provide a flow of heated fluid through the first channel and the heating channel, the flow of heated fluid through the heating channel having a main flow direction along a longitudinal direction of the wind turbine blade, and wherein the blade de-icing system is configured to influence the flow of heated fluid through the heating channel resulting in a rotational flow of heated fluid around the main flow direction. The rotational flow is rotational from a suction side to a pressure side at the leading edge.

Description

Technical Field

[0001] This invention relates to a de-icing system for wind turbine blades. Background Technology

[0002] When wind turbines operate in cold weather conditions, the potential accumulation of ice on the turbine blades poses a challenge to turbine performance. Firstly, any ice formation on the blade surface will disrupt blade aerodynamics, which can lead to reduced turbine efficiency and / or increased operating noise levels. Secondly, ice detached from the blade surface may pose a risk of falling off. In this regard, wind turbine blades are often equipped with systems in such locations to provide ice prevention and / or removal.

[0003] In addition to electric heating systems and mechanical de-icing systems embedded in the blades, it is known to provide hot air de-icing systems that operate on the principle of supplying heated air to the interior of the wind turbine blades to raise the surface temperature of the blades above freezing. An example of such a hot air de-icing system can be found in U.S. Patent Application Publication No. US 2013 / 0106108.

[0004] The purpose of this invention is to provide a de-icing system that offers improved performance compared to existing technologies. Summary of the Invention

[0005] The purpose of this invention is to provide a wind turbine blade with a de-icing system and a method for de-icing the wind turbine blade, which provides more efficient de-icing for the wind turbine blade. In particular, the invention provides more efficient heat transfer to the casing of the wind turbine blade, especially near the leading edge of the wind turbine blade, which is particularly prone to ice formation.

[0006] Therefore, a wind turbine blade with a blade de-icing system is disclosed. The wind turbine blade includes: a root end and a tip end, a leading edge and a trailing edge, a suction side and a pressure side, and an internal leading edge cavity between the leading edge and a back surface, said back surface being formed by at least one internal shear web or a sparsity side of a spar extending between the suction side and the pressure side.

[0007] The blade de-icing system includes a first channel extending longitudinally from a first position to a second position. The second position is located between the tip of the blade and the first position. The blade de-icing system also includes a heating channel extending longitudinally along the leading edge of the wind turbine blade from the second position to the first position. The heating channel and the first channel are fluidly connected.

[0008] The blade de-icing system is arranged to provide flow of heated fluid through the first channel and the heating channel. The flow of heated fluid through the heating channel has a main flow direction along the longitudinal direction of the wind turbine blade. The blade de-icing system is further configured to influence the flow of heated fluid through the heating channel, causing the heated fluid to rotate around the main flow direction.

[0009] A method for de-icing wind turbine blades (such as the disclosed wind turbine blade) is also disclosed, the wind turbine blade comprising: a root end and a tip end, a leading edge and a trailing edge, a suction side and a pressure side, and an internal leading edge cavity between the leading edge and a back surface, the back surface being formed by at least one internal shear web or a sparsity side of a spar extending between the suction side and the pressure side. The wind turbine blade further includes a first channel extending longitudinally from a first position to a second position, wherein the second position is between the tip end and the first position. The wind turbine blade further includes a heating channel extending longitudinally along the leading edge of the wind turbine blade from the second position to the first position, the heating channel and the first channel being fluidly connected.

[0010] The method includes: providing a flow of heated fluid through a first channel and a heating channel, the flow of heated fluid through the heating channel having a main flow direction along the longitudinal direction of the wind turbine blade; and influencing the flow of heated fluid through the heating channel to cause the heated fluid to rotate around the main flow direction.

[0011] Providing a rotating flow of heated fluid through the heating channel can lead to increased turbulence and velocity of the fluid near the inner part of the casing, thereby providing more efficient heat transfer from the heated fluid to the casing of the wind turbine blades.

[0012] Rotating flow can be rotation in any direction. Rotating flow can be rotation from the pressure side to the suction side at the leading edge. Rotating flow can be rotation from the suction side to the pressure side at the leading edge. On the suction side, for example near the leading edge, icing may be more likely; therefore, it may be advantageous to guide the rotating flow from the suction side to the pressure side at the leading edge, for example, to allow increased heat transfer on the suction side.

[0013] The heated fluid used in the method and de-icing system can be a gas or a liquid. For example, the heated fluid used in the method and de-icing system can be hot air, steam, or a de-icing fluid.

[0014] A first channel extends from a first position to a second position. A heating channel extends from the second position to the first position. The first position may be near the root of the wind turbine blade, for example, the root end. The second position may be near the tip of the wind turbine blade, for example, the tip end. The second position is between the tip end and the first position. The first position is between the root end and the second position.

[0015] Wind turbine blades, for example, a de-icing system for wind turbine blades may include a heating device. A wind turbine blade de-icing system, for example, may include a circulation device. The circulation device and the heating device may be combined in a heating and circulation device; for example, the circulation device may include a heating device, and / or the heating device may include a circulation device. The circulation device and / or heating device may be located at a first location, for example, near the root of the wind turbine blade. Alternatively, the wind turbine may utilize a central heating and / or circulation device, in which case, depending on the circumstances, the heating and / or circulation device may be located in the hub or nacelle of the wind turbine and connected to the de-icing system of each wind turbine blade.

[0016] The circulation device can be configured to provide a rotating flow of heated fluid through a heating channel. For example, the circulation device can be configured to circulate fluid into a heating channel that has an angle with the longitudinal direction of the wind turbine blades near the housing. Providing a rotating flow with the circulation device can be particularly useful if the circulation device circulates fluid directly into the heating channel (e.g., at a first location).

[0017] The flow of the heated fluid can be provided from a second position to a first position through a heating channel. For example, a blade de-icing system can be arranged to provide the flow of heated fluid from a second position to a first position through a heating channel. The flow of the heated fluid can also be provided from a first position through a first channel to a second position, and from a second position through a heating channel to a first position. For example, a blade de-icing system can be arranged to provide the flow of heated fluid from a first position through a first channel to a second position, and the flow of heated fluid from a second position through a heating channel to a first position. The flow of the heated fluid can also be provided from a second position through a heating channel to a first position, and from a first position through a first channel to a second position. For example, a blade de-icing system can be arranged to provide the flow of heated fluid from a second position through a heating channel to a first position, and the flow of heated fluid from a first position through a first channel to a second position.

[0018] Alternatively, the flow of the heated fluid may be provided from a first position to a second position through a heating channel. For example, a blade de-icing system may be arranged to provide the flow of heated fluid from a first position to a second position through a heating channel. The flow of the heated fluid may be provided from a first position through a heating channel to a second position, and from a second position through a first channel to a first position. For example, a blade de-icing system may be arranged to provide the flow of heated fluid from a first position through a heating channel to a second position, and the flow of heated fluid from a second position through a first channel to a first position. The flow of the heated fluid may be provided from a second position through a first channel to a first position, and from a first position through a heating channel to a second position. For example, a blade de-icing system may be arranged to provide the flow of heated fluid from a second position through a first channel to a first position, and the flow of heated fluid from a first position through a heating channel to a second position.

[0019] The leading edge cavity may form a heating channel. The leading edge cavity may form a portion of the heating channel; for example, the heating channel may include multiple heating channel portions. For instance, the heating channel may include a first heating channel portion between the leading edge cavity and the first position, and / or the heating channel may include a second heating channel portion between the leading edge cavity and the second position.

[0020] The back surface of the leading edge cavity may be formed by a shear web, for example, by a leading edge shear web. The back surface of the leading edge cavity may also be formed by the spar side of a spar, for example, by the leading edge spar side. The back surface may separate the heating channel from the first channel.

[0021] The first channel may be an insulated channel. For example, the first channel may be insulated to avoid or at least reduce heat loss from the fluid inside the first channel, for example, to conserve heat for the fluid supplied in the heating channel.

[0022] The first channel may be disposed outside the leading edge cavity, for example, between the back surface of the leading edge cavity and the trailing edge. For example, the first channel may be disposed in the space between two shear webs (e.g., the leading edge shear web and the trailing edge shear web), or the first channel may be disposed in the space between two spar sides of the spar (e.g., the leading edge spar side and the trailing edge spar side of the spar).

[0023] Alternatively, the first channel may be located inside the leading edge cavity. For example, the first channel may be configured as a tube inside the leading edge cavity.

[0024] One or more holes, for example, multiple holes, may be provided between the first channel and the heating channel, for example, to provide fluid connection between the first channel and the heating channel. Multiple holes may be distributed along the longitudinal direction of the wind turbine blade.

[0025] Multiple orifices can be configured to guide the heated fluid into a heating channel in a first direction, for example, to provide a swirling flow of the heated fluid in the heating channel. The first direction can form a first angle with a second direction between the orifice and its leading edge. The first angle can be greater than 10 degrees, for example greater than 20 degrees, for example greater than 30 degrees, for example greater than 40 degrees, for example 45 degrees. The first direction can be towards the suction side. The first direction can be towards the pressure side. The multiple orifices may include fluid guiding elements. The fluid guiding elements can be configured to guide the heated fluid in the first direction. The fluid guiding elements can be made of foam blocks. The fluid guiding elements can form nozzles and channels to guide the heated fluid. By guiding fluid from the orifices in the direction forming the angle, the heated fluid leaving the orifices is not directly guided into the main flow, and thus, another advantage is that it reduces the deflection of the heated fluid from the orifices caused by the main flow. Therefore, the temperature of the heated fluid reaching the leading edge is higher than the temperature if the orifices were directly guided into the main flow. Thus, the heated fluid from the orifices can provide increased localized heating of the housing near the orifices.

[0026] Multiple orifices can be positioned at a first orifice distance from the suction side and a second orifice distance from the pressure side. The first and second orifice distances can be selected, for example, to provide swirling flow of the heated fluid within the heating channel. For example, the second orifice distance can be longer than the first orifice distance, such as more than twice the first orifice distance. A second orifice distance longer than the first orifice distance can provide swirling flow at the leading edge along the suction side and from the suction side to the pressure side. Alternatively, the first orifice distance can be longer than the second orifice distance, such as more than twice the first orifice distance. A first orifice distance longer than the second orifice distance can provide swirling flow at the leading edge along the pressure side and from the pressure side to the suction side.

[0027] The heating channel may include one or more guiding structures, for example, multiple guiding structures distributed along the longitudinal direction of the heating channel. One or more guiding structures may be configured to influence the flow of the heated fluid through the heating channel, causing the heated fluid to rotate about the main flow direction. For example, the guiding structure may include a guiding surface having a normal to the guiding surface. The normal to the guiding surface may form a guiding angle with the main flow direction. The guiding angle may be greater than 0 degrees and less than 90 degrees, for example, between 20 and 70 degrees, between 40 and 50 degrees, or 45 degrees. Attached Figure Description

[0028] Embodiments of this disclosure will be described in more detail below with reference to the accompanying drawings. These figures illustrate one way of implementing the invention and are not to be construed as limiting oneself to other possible embodiments falling within the scope of the appended claims.

[0029] Figure 1This is a schematic diagram illustrating an exemplary wind turbine.

[0030] Figure 2 This is a schematic diagram illustrating an exemplary wind turbine blade.

[0031] Figure 3 This is a schematic diagram illustrating a longitudinal cross-sectional view of an exemplary wind turbine blade.

[0032] Figure 4a This is a schematic diagram illustrating the cross-section of an exemplary wind turbine blade.

[0033] Figure 4b This is a schematic diagram illustrating the cross-section of an exemplary wind turbine blade.

[0034] Figure 4c This is a schematic diagram illustrating the cross-section of an exemplary wind turbine blade.

[0035] Figure 5a This is a schematic diagram illustrating a longitudinal cross-sectional view of the shear web or spars side of an exemplary wind turbine blade.

[0036] Figure 5b This is a schematic diagram illustrating a longitudinal cross-sectional view of the shear web or spars side of an exemplary wind turbine blade.

[0037] Figure 5c This is a schematic diagram illustrating a longitudinal cross-sectional view of the shear web or spars side of an exemplary wind turbine blade, and

[0038] Figure 6 This is a flowchart of an exemplary method. Detailed Implementation

[0039] Figure 1 The illustration depicts a conventional modern upwind wind turbine 2 based on the so-called "Danish concept," which has a tower 4, a nacelle 6, and a rotor with a generally horizontal rotor shaft. The rotor includes a hub 8 and three blades 10 extending radially from the hub 8, each blade having a blade root 16 closest to the hub and a blade tip 14 furthest from the hub 8.

[0040] Figure 2 A schematic diagram of an exemplary wind turbine blade 10 is shown. The wind turbine blade 10 has the shape of a conventional wind turbine blade, having a root end 17 and a tip end 15, and includes: a root region 30 closest to the hub, a shaped or airfoil region 34 furthest from the hub, and a transition region 32 between the root region 30 and the airfoil region 34. The blade 10 includes a leading edge 18 and a trailing edge 20, wherein when the blade is mounted on the hub, the leading edge 18 faces the direction of rotation of the blade 10, and the trailing edge 20 faces the opposite direction to the leading edge 18.

[0041] Airfoil region 34 (also called the forming region) has an ideal or near-ideal blade shape for generating lift, while root region 30 has a generally circular or elliptical cross-section for structural considerations, which, for example, makes it easier and safer to mount the blade 10 to the hub. The diameter (or chord) of root region 30 may be constant throughout root region 30. Transition region 32 has a transition profile that gradually changes from the circular or elliptical shape of root region 30 to the airfoil profile of airfoil region 34. The chord length of transition region 32 typically increases with increasing distance r from the hub. Airfoil region 34 has an airfoil profile with a chord extending between the leading edge 18 and trailing edge 20 of blade 10. The width of the chord decreases with increasing distance r from the hub.

[0042] The shoulder 40 of the blade 10 is defined as the location where the blade 10 has its maximum chord length. The shoulder 40 is typically located at the boundary between the transition region 32 and the airfoil region 34.

[0043] It should be noted that the chords of different sections of the blade are not usually located in a common plane because the blade can twist and / or bend (i.e., pre-bend), thus providing a chord plane with corresponding twisted and / or bent lines, which is most common in cases where the local velocity of the blade depends on the radius from the hub in order to compensate for the local velocity of the blade.

[0044] The wind turbine blade 10 includes a blade shell. The blade shell may include two blade shell components, typically made of fiber-reinforced polymer, a first blade shell component 24 and a second blade shell component 26. The first blade shell component 24 is typically a pressure-side or upwind blade shell component. The second blade shell component 26 is typically a suction-side or downwind blade shell component. The first blade shell component 24 and the second blade shell component are typically bonded together along a joint line or adhesive joint 28 extending along the trailing edge 20 and leading edge 18 of the blade 10. Typically, the root ends of the blade shell components 24, 26 have a semi-circular or semi-elliptical external cross-sectional shape.

[0045] The wind turbine blade 10 further includes at least one internal shear-resistant web or spars on the spars side of a spar extending between the suction side and the pressure side of the wind turbine blade 10 (e.g., see...). Figure 4a ).

[0046] Figure 3A schematic longitudinal sectional view of an exemplary wind turbine blade 10, shown from the suction side 54 to the pressure side 52, is illustrated. The exemplary wind turbine blade 10 has a de-icing system. The wind turbine blade 10 has a blade tip 14 and a blade root 16. The wind turbine blade 10 has a tip end 15 and a root end 17. The wind turbine blade 10 further includes two shear webs 22, 24 extending between the suction and pressure sides of the wind turbine blade 10, a leading-edge shear web 22 and a trailing-edge shear web 24. Alternatively, the wind turbine blade 10 may include a sparsity, and the sparsity side of the sparsity may replace the illustrated shear webs 22, 24 (e.g., see...). Figure 4b An internal leading edge cavity 78 may be formed between the leading edge 18 and the back surface 79 (e.g., leading edge shear web 22).

[0047] The wind turbine blade 10 includes a first channel 70 extending longitudinally from a first position P1 to a second position P2. The wind turbine blade 10 also includes a heating channel 72 extending longitudinally along the leading edge 18 of the blade from the second position P2 to the first position P1. The second position is located between the tip 15 and the first position P1. The first position P1 is located between the root end 17 and the second position P2. The first position P1 is closer to the root end 17. The second position P2 is closer to the tip 15.

[0048] The first channel 70 may be arranged between the leading edge shear web 22 and the trailing edge shear web 24. The heating channel 72 may be arranged in the leading edge cavity 78. The first channel 70 and the heating channel 72 may be fluidly connected, for example, through the hole 60.

[0049] The blade 10 has a circulation device 80, such as a heating and circulation device. The circulation device 80 may be located near the root end 17 of the blade. Alternatively, the circulation device 80 may be located near the tip end 15. The circulation device 80 may be arranged closer to the leading edge 18 than the trailing edge 20. Alternatively, the circulation device 80 may be arranged closer to the trailing edge 20 than the leading edge 18. Alternatively, the circulation device 80 may be arranged as close to the trailing edge 20 as it is to the leading edge 18. The circulation device 80 provides flow of heated fluid through the first channel 70 and the heating channel 72. The circulation device 80 may be configured to heat the fluid.

[0050] As illustrated, the flow direction has a main flow direction 74, which can be guided from the root end 17 through the first channel 70 to the tip end 15, and from the tip end 15 through the heating channel 72 to the root end 17. Alternatively, the main flow direction 74 can be in the opposite direction, i.e., from the blade root end 17 through the heating channel 72 to the blade tip end 15, and from the blade tip end 15 through the first channel 70 to the blade root end 17.

[0051] The leading-edge shear web 22 includes a plurality of holes 60. The plurality of holes 60 may be distributed along the longitudinal direction of the wind turbine blade 10. These holes allow the flow of heated fluid between the first channel 70 and the heating channel 72, for example, from the first channel 70 to the heating channel 72. The holes 60 may be configured to influence the flow of heated fluid through the heating channel 72, resulting in rotational flow of the heated fluid about the main flow direction 74 (e.g., see...). Figures 4a to 4c Alternatively or additionally, the circulation device 80 may be configured to influence the flow of the heated fluid through the heating channel 72, causing the heated fluid to rotate around the main flow direction 74. Alternatively or additionally, the heating channel 72 may be provided with a plurality of guide structures distributed along the longitudinal direction of the heating channel 72 (e.g., see...). Figure 5c ).

[0052] Figure 4a This is a schematic diagram illustrating the cross-section of a wind turbine blade 10 with a de-icing system, for example, with... Figure 3 The cross-section of a wind turbine blade 10 is illustrated in connection with the diagram. The wind turbine blade 10 has a leading edge 18, a trailing edge 20, a pressure side 52, and a suction side 54. The wind turbine blade 10 includes a leading-edge shear web 22 and a trailing-edge shear web 24. Alternatives for the shear webs 22 and 24 may be spars, such as… Figure 4b As illustrated in the figure. The de-icing system includes a first channel 70 defined by shear webs 22, 24 and a heating channel 72. The heating channel 72 may be an internal leading edge cavity 78 between the leading edge 18 and the back surface 79 (e.g., the leading edge shear web 22), or form part of it.

[0053] The leading-edge shear web 22 includes a hole 60, such as one of a plurality of holes. As illustrated, the hole 60 allows flow of heated fluid between a first channel 70 and a heating channel 72, for example, from the first channel 70 to the heating channel 72. The hole 60 is configured to influence the flow of heated fluid through the heating channel 72, resulting in a rotational flow 76 of the heated fluid along the heating channel 72 about a main flow direction. As illustrated, the rotational flow 76 may be a rotation from the suction side 54 to the pressure side 52 at the leading edge 18. Alternatively, the rotational flow 76 may be a rotation from the pressure side 52 to the suction side 54. As illustrated, the hole 60 may include a fluid guiding element 62 to guide the flow of heated fluid. The direction of flow may be in a first direction 102 and form an angle α with a second direction 104 between the hole 60 and the leading edge 18. For example, the angle α may be greater than 10 degrees.

[0054] Figure 4b This is a schematic diagram illustrating the cross-section of a wind turbine blade 10' with a de-icing system, for example, with... Figure 3 The cross-section of the wind turbine blade 10 is illustrated in connection with this diagram. In addition to the wind turbine blade 10', it includes a sparsity 26, instead of... Figure 4a In addition to the shear web of the wind turbine blade 10 Figure 4b The 10' wind turbine blade is equivalent to Figure 4a The wind turbine blade 10. The spars 26 include a leading-edge sparsity side 23, replacing... Figure 4a The leading edge shear web 22 and trailing edge sparse side 25 of the wind turbine blade 10 replace Figure 4a The trailing edge shear web 24 of the wind turbine blade. The leading edge spar side 23 of the spar includes a hole 60.

[0055] Figure 4c This is a schematic diagram illustrating the cross-section of a wind turbine blade 10 with a de-icing system, for example, with... Figure 3 The cross-section of the wind turbine blade 10 is illustrated in connection with this diagram. Figure 4c The wind turbine blade 10 is illustrated as having shear-resistant webs 22 and 24. Alternatively, the wind turbine blade 10 can be implemented using a sparsity with spars on the spar side, as shown in the diagram. Figure 4b As explained in relation to other factors.

[0056] The de-icing system may include a first channel 70 defined by shear webs 22, 24 and a heating channel 72. The heating channel 72 may be an internal leading edge cavity 78 between the leading edge 18 and the back surface 79 (e.g., the leading edge shear web 22), or form part of it.

[0057] The leading edge shear web 22 includes a hole 60', for example, one of a plurality of holes. As illustrated, the hole 60' allows flow of heated fluid between a first channel 70 and a heating channel 72, for example, from the first channel 70 to the heating channel 72. The hole 60' is configured to influence the flow of heated fluid through the heating channel 72, causing the heated fluid to rotate 76 along the heating channel 72 about a main flow direction. As illustrated, the rotating flow 76 may be a rotation from the suction side 54 to the pressure side 52 at the leading edge 18. Alternatively, the rotating flow 76 may be a rotation from the pressure side 52 to the suction side 54. The hole 60' is located at a first hole distance D1 from the suction side 54 and a second hole distance D2 from the pressure side 52. The first hole distance D1 and the second hole distance may be different in order to influence the flow of fluid through the heating channel 72, causing the heated fluid to rotate 76 about a main flow direction 74. For example, as illustrated, the distance D2 of the second orifice can be longer than the distance D1 of the first orifice, resulting in a rotating flow 76 from the suction side 54 to the pressure side 52 at the leading edge 18. Alternatively, the distance of the second orifice can be shorter than the distance D1 of the first orifice. Thus, the position of the orifice 60' affects the flow of the heated fluid in the heating channel 72, resulting in a rotating flow 76 of the heated fluid about the main flow direction 74.

[0058] Figure 5aThis is a schematic diagram illustrating a wind turbine blade (e.g., as shown in the diagram). Figure 4a The longitudinal section view of an exemplary shear web 22 or sparsity side 23 of a wind turbine blade (as illustrated in Figure 4b) is shown. The longitudinal section view is seen from the leading edge to the trailing edge. The shear web 22 or sparsity side 23 includes a plurality of holes 60 distributed along the longitudinal direction of the wind turbine blade. The holes 60 include fluid guiding elements 62 to guide the heated fluid from a first channel 70 into a heating channel 72. The holes 60 are configured to guide the heated fluid into the heating channel 72 in a first direction, which forms a first angle (not shown) with a second direction between the holes 60 and the leading edge 18. Thus, the heated fluid can flow in a rotating flow 76 about a main flow direction 74 and can rotate from the suction side 54 to the pressure side 52 at the leading edge 18.

[0059] Figure 5b This is a schematic diagram illustrating a wind turbine blade (e.g., as shown in the diagram). Figure 4c The longitudinal section view of an exemplary shear web 22 or sparsity side 23 (as illustrated in the diagram of a wind turbine blade) is shown. The longitudinal section view is seen from the leading edge to the trailing edge. The shear web 22 or sparsity side 23 may include a plurality of holes 60' distributed along the longitudinal direction of the wind turbine blade. The holes 60' are located at a first hole distance D1 from the suction side 54 and a second hole distance D2 from the pressure side 52. The first hole distance D1 and the second hole distance are different in order to influence the flow of fluid through the heating channel 72, resulting in a swirling flow 76 of the heated fluid around the main flow direction 74. For example, as illustrated, the second hole distance D2 may be longer than the first hole distance D1, for example, resulting in a swirling flow 76 from the suction side 54 to the pressure side 52 at the leading edge, and a swirling flow 76 from the pressure side to the suction side 54 at the back surface of the heating channel 72 (e.g., the shear web 22 or sparsity side 23). Alternatively, the distance between the second orifice and the first orifice can be shorter than the distance D1, which will provide a reverse swirling flow. Thus, the position of the orifice 60' affects the flow of the heated fluid in the heating channel 72, resulting in a swirling flow 76 of the heated fluid around the main flow direction 74.

[0060] Figure 5cThis is a schematic diagram illustrating a longitudinal cross-sectional view of an exemplary shear web 22 or sparse side 23 of a wind turbine blade. The longitudinal cross-sectional view is seen from the leading edge to the trailing edge. The shear web 22 or sparse side 23 may include a plurality of guide structures 90 distributed along the longitudinal direction of the shear web 22 or sparse side 23 (e.g., along the longitudinal direction of the heating channel 72). The guide structures 90 may be configured to influence the flow of heated fluid through the heating channel 72, resulting in a rotating flow 76 of the heated fluid about a main flow direction 74. The guide structures may be configured such that the rotating flow 76 can rotate from the suction side 54 to the pressure side 52 at the leading edge, and from the pressure side to the suction side 54 at the back surface of the heating channel 72 (e.g., the shear web 22 or sparse side 23). The guide structure 90 includes a guide surface 92. The guide surface normal n forms a guide surface angle with the main flow direction 74. Guiding surface angle It can be greater than 0 degrees and less than 90 degrees, for example, the guide surface angle. It can be 45 degrees.

[0061] Figure 6 This illustrates the use of diagrams for wind turbine blades (e.g., any diagram from the previous figures, such as...). Figure 2 A flowchart of an exemplary method 200 for de-icing wind turbine blades. Method 200 includes: providing a flow 202 of heated fluid through a first channel and a heating channel, the flow of heated fluid having a main flow direction along the longitudinal direction of the wind turbine blade. For example, the heated fluid may be provided by a heating and circulation device. Method 200 further includes: influencing 204 the flow of heated fluid through heating channel 72, causing the heated fluid to rotate about the main flow direction. For example, the main flow may be influenced by providing one or more orifices having fluid guiding elements (e.g., see...). Figure 4a , Figure 4b or Figure 5a ), shift one or more orifices toward the pressure side or suction side (e.g., see Figure 4c (or 5b), or provide one or more boot structures (e.g., see 5b). Figure 5c ).

[0062] It will be understood that the above examples are not mutually exclusive and can be combined. Individual features of the above embodiments can be combined with features of any other embodiment. For example, the above examples for influencing the flow of heated fluid through a heating channel can be combined to cause the heated fluid to rotate about the main flow direction. For example, a wind turbine blade can be implemented such that, as with Figure 4a , Figure 4b and Figure 5a The fluid guiding element 62 is explained in relation to, as with, Figure 4c and Figure 5bThe associated hole combination to explain the offset, and / or with, as with Figure 5c The 90-combination of the guiding structure is explained in relation to each other.

[0063] Wind turbine blades with the de-icing system described above offer several advantages over the prior art. This invention provides a more efficient and effective de-icing system, resulting in reduced stress and strain, as well as weight requirements, for the entire wind turbine blade structure.

[0064] It will be understood that common elements across different embodiments of the invention have been given the same reference numerals in the drawings. It will be further understood that the individual features shown in the different embodiments of the invention are not limited to those specific embodiments and can be suitably reproduced in any of the other shown embodiments.

[0065] The invention has been described with reference to preferred embodiments. However, the scope of the invention is not limited to the illustrated embodiments, and changes and modifications can be made without departing from the scope of the invention.

[0066] Exemplary wind turbine blades and methods are listed in the following items:

[0067] 1. A wind turbine blade with a blade de-icing system, the wind turbine blade comprising: a root end and a tip end, a leading edge and a trailing edge, a suction side and a pressure side, and an internal leading edge cavity between the leading edge and a back surface, the back surface being formed by at least one internal shear web or a sparsity side extending between the suction side and the pressure side, the blade de-icing system comprising:

[0068] A first channel extends longitudinally from a first position to a second position, wherein the second position is located between the distal end and the first position; and

[0069] A heating channel extends longitudinally from the second position to the first position along the leading edge of the wind turbine blade, and the heating channel and the first channel are fluidly connected;

[0070] The blade de-icing system is arranged to provide flow of heated fluid through the first channel and the heating channel. The flow of heated fluid through the heating channel has a main flow direction along the longitudinal direction of the wind turbine blade. The blade de-icing system is configured to influence the flow of heated fluid through the heating channel, causing the heated fluid to rotate around the main flow direction.

[0071] 2. The wind turbine blade according to Item 1, including a heating device and / or a circulation device disposed at a first location.

[0072] 3. The wind turbine blade according to any one of the preceding items, wherein the blade de-icing system is arranged to provide flow of heated fluid from a first position through a first channel to a second position, and flow of heated fluid from the second position through a heating channel to the first position.

[0073] 4. The wind turbine blade according to any one of the preceding items, wherein the leading edge cavity forms a heating channel.

[0074] 5. The wind turbine blade according to any one of the foregoing items, wherein the back surface separates the heating channel and the first channel.

[0075] 6. The wind turbine blade according to any one of the preceding items, wherein the first channel is arranged in the space between the leading edge shear web or spar side and the trailing edge shear web or spar side.

[0076] 7. The wind turbine blade according to any one of items 1-4, wherein the first channel is arranged inside the leading edge cavity.

[0077] 8. The wind turbine blade according to any one of the preceding items, wherein the swirling flow is a rotation from the suction side to the pressure side at the leading edge.

[0078] 9. The wind turbine blade according to any one of the preceding items, comprising a plurality of holes between a first channel and a heating channel, the plurality of holes being distributed along the longitudinal direction of the wind turbine blade.

[0079] 10. The wind turbine blade according to Item 9, wherein a plurality of holes are configured to guide the heated fluid into a heating channel in a first direction, the first direction forming a first angle with a second direction between the holes and the leading edge.

[0080] 11. The wind turbine blade according to Project 10, wherein the first angle is greater than 10 degrees.

[0081] 12. The wind turbine blade according to any one of items 9-11, wherein the plurality of orifices include fluid guiding elements for guiding heated fluid in a first direction.

[0082] 13. The wind turbine blade according to any one of items 9-12, wherein a plurality of holes are positioned at a distance from a first hole on the suction side and at a distance from a second hole on the pressure side, wherein the distance from the second hole is longer than the distance from the first hole.

[0083] 14. The wind turbine blade according to Project 13, wherein the distance between the second holes is more than twice the distance between the first holes.

[0084] 15. The wind turbine blade according to any one of the preceding items, wherein the heating channel includes a plurality of guide structures distributed along the longitudinal direction of the heating channel, the plurality of guide structures being configured to influence the flow of the heated fluid passing through the heating channel, causing the heated fluid to rotate around the main flow direction.

[0085] 16. The wind turbine blade according to Item 15, wherein the guiding structure includes a guiding surface having a guiding surface normal, the guiding surface normal forming a guiding angle with the main flow direction, the guiding angle being greater than 0 degrees and less than 90 degrees.

[0086] 17. A method for de-icing a wind turbine blade, the wind turbine blade comprising: a root end and a tip end, a leading edge and a trailing edge, a suction side and a pressure side, and an internal leading edge cavity between the leading edge and a back surface, the back surface being formed by a spar side of at least one internal shear web or spar extending between the suction side and the pressure side, the wind turbine blade further comprising a first channel extending longitudinally from a first position to a second position, wherein the second position is between the tip end and the first position, and the wind turbine blade further comprising a heating channel extending longitudinally along the leading edge of the wind turbine blade from the second position to the first position, the heating channel and the first channel being fluidly connected, the method comprising:

[0087] - Provides flow of heated fluid through the first channel and the heating channel, the flow of heated fluid through the heating channel having a main flow direction along the longitudinal direction of the wind turbine blades, and

[0088] - It affects the flow of the heated fluid through the heating channel, causing the heated fluid to rotate around the main flow direction.

[0089] Reference Symbol List

[0090] 10 blades

[0091] 14. Leaf tips

[0092] 15 distal end

[0093] 16. Leaf base

[0094] 17. Root end

[0095] 18. Predestined Fate

[0096] 20 trailing edge

[0097] 22 Leading edge shear web

[0098] 23 Leading edge spars side

[0099] 24 Trailing edge shear web

[0100] 25 Trailing edge spars side

[0101] 26 wing spars

[0102] 52 Pressure side

[0103] 54 Suction Side

[0104] 60 holes

[0105] 62 Fluid guiding element

[0106] α First angle

[0107] 70 First Channel

[0108] 72 heating channels

[0109] 74 Main flow direction

[0110] 76 Rotational Flow

[0111] 78 Anterior edge cavity

[0112] 79 Back surface

[0113] 80 Heating and circulation device

[0114] 90 Guiding Structure

[0115] 92 Guiding Surface

[0116] n Guide surface normal

[0117] Leading angle

[0118] D1 Distance of the first hole

[0119] D2 Second Hole Distance

[0120] P1 First Position

[0121] P2 Second Position

Claims

1. A wind turbine blade with a blade de-icing system, the wind turbine blade comprising: The blade de-icing system comprises: a root end and a tip end, a leading edge and a trailing edge, a suction side and a pressure side, and an internal leading edge cavity between the leading edge and the back surface, the back surface being formed by at least one internal shear web or a spar side of a spar extending between the suction side and the pressure side; the blade de-icing system includes: A first channel extends longitudinally from a first position to a second position, wherein the second position is between the distal end and the first position; and A heating channel extends longitudinally from the second position to the first position along the leading edge of the wind turbine blade, and the heating channel and the first channel are fluidly connected. The blade de-icing system is arranged to provide flow of heated fluid through the first channel and the heating channel, the flow of heated fluid through the heating channel having a main flow direction along the longitudinal direction of the wind turbine blade, and wherein the blade de-icing system is configured to influence the flow of heated fluid through the heating channel, causing the heated fluid to rotate around the main flow direction. The rotational flow is either a rotation from the suction side to the pressure side at the leading edge, or a rotation from the pressure side to the suction side at the leading edge.

2. The wind turbine blade according to claim 1, comprising a heating device and / or a circulation device disposed at the first position.

3. The wind turbine blade according to claim 1 or 2, wherein, The blade de-icing system is arranged to provide a flow of heated fluid from the first position through the first channel to the second position, and a flow of heated fluid from the second position through the heating channel to the first position.

4. The wind turbine blade according to claim 1 or 2, wherein, The leading edge cavity forms the heating channel.

5. The wind turbine blade according to claim 1 or 2, wherein, The back surface separates the heating channel from the first channel.

6. The wind turbine blade according to claim 1 or 2, wherein, The first channel is arranged in the space between the front edge shear web or wing beam side and the rear edge shear web or wing beam side.

7. The wind turbine blade according to claim 1 or 2, wherein, The first channel is arranged inside the leading edge cavity.

8. The wind turbine blade according to claim 1 or 2, comprising a plurality of holes between the first channel and the heating channel, the plurality of holes being distributed along the longitudinal direction of the wind turbine blade.

9. The wind turbine blade according to claim 8, wherein, The plurality of holes are configured to guide the heated fluid into the heating channel in a first direction, the first direction forming a first angle with a second direction between the holes and the leading edge.

10. The wind turbine blade according to claim 9, wherein, The first angle is greater than 10 degrees.

11. The wind turbine blade according to claim 9 or 10, wherein, The plurality of orifices include fluid guiding elements to guide the heated fluid in the first direction.

12. The wind turbine blade according to claim 8, wherein, The plurality of holes are located at a first hole distance from the suction side and at a second hole distance from the pressure side, wherein the second hole distance is longer than the first hole distance.

13. The wind turbine blade according to claim 12, wherein, The distance of the second hole is more than twice the distance of the first hole.

14. The wind turbine blade according to claim 1 or 2, wherein, The heating channel includes a plurality of guide structures distributed along the longitudinal direction of the heating channel, the plurality of guide structures being configured to influence the flow of the heated fluid passing through the heating channel, causing the heated fluid to rotate around the main flow direction.

15. The wind turbine blade according to claim 14, wherein, The guiding structure includes a guiding surface with a guiding surface normal. The guiding surface normal forms a guiding angle with the main flow direction, and the guiding angle is greater than 0 degrees and less than 90 degrees.

16. A method for de-icing wind turbine blades, the wind turbine blades comprising: The wind turbine blade includes a root end and a tip end, a leading edge and a trailing edge, a suction side and a pressure side, and an internal leading edge cavity between the leading edge and a back surface, the back surface being formed by at least one internal shear web or a spar side of a spar extending between the suction side and the pressure side. The wind turbine blade further includes a first channel extending longitudinally from a first position to a second position, wherein the second position is between the tip end and the first position. The wind turbine blade further includes a heating channel extending longitudinally along the leading edge of the wind turbine blade from the second position to the first position, the heating channel and the first channel being fluidly connected. The method includes: - Provides flow of heated fluid through the first channel and the heating channel, wherein the flow of heated fluid through the heating channel has a main flow direction along the longitudinal direction of the wind turbine blade, and - This affects the flow of the heated fluid through the heating channel, causing the heated fluid to rotate around the main flow direction. The rotational flow is either a rotation from the suction side to the pressure side at the leading edge, or a rotation from the pressure side to the suction side at the leading edge.

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