Blade root sample and manufacturing method thereof

Abstract

The invention relates to a blade root sample and a manufacturing method thereof. The blade root sample comprises a sample body and a core body; the core body is arranged in the sample body, the core body comprises at least one core shaft, and the core shaft is provided with a central axis extending along a first direction; in the second direction and / or the third direction, the projection of the core shaft is symmetrical along the central axis of the core shaft; included angles are formed between every two of the first direction, the second direction and the third direction. According to the blade root sample and the manufacturing method thereof provided by the embodiment of the invention, the condition that the blade root sample is damaged due to stress concentration when the blade root sample is subjected to external force can be effectively reduced, and normal test is ensured.

Description

Technical Field

[0001] The present application relates to the technical field of wind turbine blades, and in particular to a blade root specimen and a method for manufacturing the same. Background Art

[0002] Wind turbine blades are an important part of wind turbines. As the power of wind turbines increases, the trend of wind turbine blades becoming larger has become more obvious, and the radial size of the blade root pitch circle has gradually increased.

[0003] However, the premise of increasing the blade root pitch circle is to ensure the bearing capacity of the blade root connection. Therefore, before the blade root pitch circle with increased size is manufactured and used, it is necessary to conduct tests to verify its safety. During the test, it is necessary to simulate a part of the circumference of the blade root pitch circle to manufacture the blade root specimen. The blade root specimen includes a roughly strip-shaped structure with a core body inside. When the blade root specimen is subjected to external force, it is found that the force uniformity at various locations is poor, which makes the blade root specimen prone to stress concentration and damage, affecting the normal progress of the test. Summary of the invention

[0004] The embodiment of the present application provides a blade root specimen and a method for manufacturing the same, which can effectively reduce the damage of the blade root specimen due to stress concentration when subjected to external force, thereby ensuring the normal progress of the test.

[0005] The embodiment of the present application provides a blade root specimen, wherein the blade root specimen comprises a specimen body and a core body; the core body is arranged inside the specimen body, the core body comprises at least one core shaft, and the core shaft has a central axis extending along a first direction;

[0006] Along the second direction and / or the third direction, the projection of the mandrel is symmetrical along its central axis;

[0007] The first direction, the second direction and the third direction have an included angle between each other.

[0008] According to one aspect of the embodiment of the present application, the sample body has a central axis extending along the first direction; along the second direction, the projection of the central axis of the sample body coincides with the projection of the central axis of the mandrel, and the projection of the sample body is symmetrical along its central axis.

[0009] According to one aspect of the embodiment of the present application, the core body includes a plurality of mandrels, and the plurality of mandrels are evenly spaced along the second direction;

[0010] Along the third direction, the projections of the mandrels are symmetrically arranged along the central axis of the sample body.

[0011] According to one aspect of the embodiment of the present application, the mandrel includes a first section and a second section arranged along a first direction, and the first section and the second section are detachably connected;

[0012] The first section is in a cylindrical structure. Along the direction away from the first section, the size of the second section along the third direction gradually decreases and the size along the second direction gradually increases.

[0013] According to one aspect of the embodiment of the present application, the first section is a threaded sleeve with a hollow interior, an insulating coating layer is provided on the outer circumference of the threaded sleeve, and the insulating coating layer is formed by insulating yarn wrapped around the outer circumference of the threaded sleeve.

[0014] According to one aspect of the embodiment of the present application, the difference between the maximum distance and the minimum distance between the outer surface of the insulating coating and the axis of the threaded sleeve is less than or equal to 2 mm.

[0015] According to one aspect of the embodiment of the present application, the second section is a solid structure made of foam material; a plug connector is formed at the end of the second section facing the first section, and the plug connector is plugged into the interior of the first section.

[0016] According to one aspect of the embodiment of the present application, the core body also includes a support member, and each of the core shafts is provided with a support member on both sides along the second direction. The support member is in close contact with the corresponding core shaft, and the two side surfaces of the support member along the third direction are respectively flush with the two side surfaces of the core shaft along the third direction.

[0017] According to one aspect of the embodiment of the present application, the core body also includes a partition, which is provided between every two adjacent core shafts, and the two sides of the partition along the second direction are respectively connected to the support members connected to the two core shafts, and the two side surfaces of the partition along the third direction are respectively flush with the two side surfaces of the core shaft along the third direction.

[0018] According to one aspect of an embodiment of the present application, the sample body includes two baffles arranged opposite to each other along the second direction and two pressure plates arranged opposite to each other along the third direction, the two baffles and the two pressure plates are alternately connected to enclose a cavity, the core body is in the cavity, and the two side surfaces of the core body along the third direction are respectively connected to the two pressure plates, and the two side surfaces of the core body along the second direction are respectively connected to the two baffles.

[0019] According to one aspect of the embodiment of the present application, the pressure plate includes a covering portion and an extension portion arranged and connected along the first direction, the two covering portions are respectively connected to the two sides of the core along the third direction, and the two extension portions are stacked and connected along the third direction.

[0020] According to one aspect of the embodiment of the present application, an end portion of the first section away from the second section protrudes from an end surface of the sample body along the first direction.

[0021] The embodiment of the present application further provides a blade root sample manufacturing method, which can be used to manufacture the blade root sample as described above. The blade root sample manufacturing method comprises:

[0022] Processing the mandrel so that the mandrel extends along a first direction and the projections of the mandrel along a second direction and / or a third direction are symmetrical along a central axis extending in the first direction;

[0023] manufacturing a core body, wherein the core body comprises at least one of the mandrels;

[0024] The core is fixed inside the sample body.

[0025] According to one aspect of an embodiment of the present application, processing the mandrel so that the core body extends along a first direction and the projections of the core body along a second direction and / or a third direction are symmetrical along a central axis extending in the first direction includes:

[0026] The first stage of processing includes:

[0027] Setting a threaded sleeve;

[0028] Winding insulating yarn on the outer circumference of the threaded sleeve to form an insulating coating layer;

[0029] The second stage of processing includes:

[0030] A solid columnar structure is made of foam material, and along a direction away from the first section, the size of the second section along the third direction gradually decreases and the size along the second direction gradually increases;

[0031] Connecting the first segment to the second segment comprises:

[0032] A plug connector is formed at the end of the second section facing the first section, and the plug connector is plugged into the interior of the first section.

[0033] According to one aspect of the embodiment of the present application, a core body is manufactured so that the core body includes at least one core shaft, including:

[0034] Arrange a plurality of the mandrels so that the plurality of mandrels are evenly spaced along the second direction;

[0035] Connecting and disposing supporting members on both sides of each mandrel along the second direction, respectively, so that both side surfaces of the supporting members along the third direction are flush with both side surfaces of the mandrel along the third direction;

[0036] A separator is arranged between every two adjacent core shafts, and both sides of the separator along the second direction are respectively connected to the support members connected to the two core shafts, and both side surfaces of the separator along the third direction are respectively flush with both side surfaces of the core shaft along the third direction.

[0037] According to one aspect of an embodiment of the present application, fixing the core body inside the sample body includes:

[0038] An assembly plane is set, and a pad is laid on the assembly plane, wherein a surface of the pad facing away from the assembly plane can be in contact with a surface of the second section of the mandrel along a third direction;

[0039] Laying a first layer so that a portion of the first layer is laid on the assembly plane and another portion of the first layer is laid on the backing plate;

[0040] A core body is arranged on the first layer, so that the first section of each core shaft is correspondingly fitted with the portion of the first layer laid on the assembly plane, and the second section of each core shaft is correspondingly fitted with the portion of the first layer laid on the backing plate;

[0041] baffles are respectively arranged on both sides of the core body along the second direction, so that the baffles are in contact with the first ply;

[0042] Laying a second layer on the side of the core and the two baffles away from the first layer, and making the second layer fit the core and the two baffles respectively;

[0043] Injecting adhesive liquid into the cavity formed by the first ply, the second ply and the two baffles;

[0044] After the adhesive liquid is solidified, the first layer and the second layer form two pressing plates.

[0045] The blade root specimen and the manufacturing method thereof provided in the embodiment of the present application can effectively improve the uniformity of the overall structure of the core shaft by making the core shaft arranged inside the core body present a symmetrical structure along the second direction and / or the third direction, thereby improving the force uniformity of the core shaft, the core body and the blade root specimen as a whole when subjected to external force, effectively reducing the damage of the blade root specimen due to stress concentration when subjected to external force, thereby ensuring the normal progress of the test. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The features, advantages and technical effects of exemplary embodiments of the present application will be described below with reference to the accompanying drawings.

[0047] Figure 1 A schematic diagram of the internal structure of a blade root sample along a second direction provided in an embodiment of the present application;

[0048] Figure 2 A schematic diagram of the internal structure of a blade root sample along a third direction provided in an embodiment of the present application;

[0049] Figure 3 A schematic structural diagram of the first section of the core shaft of the core body of the blade root sample provided in an embodiment of the present application;

[0050] Figure 4 A schematic structural diagram of a core shaft of a core body of a blade root sample provided in an embodiment of the present application;

[0051] Figure 5 A schematic structural diagram of a blade root sample provided in an embodiment of the present application along a first direction at an end of a first section of a core shaft away from a second section;

[0052] Figure 6 Schematic diagram of the testing device for the blade root sample provided in the embodiment of the present application

[0053] Figure 7 Schematic diagram of the manufacturing process of the blade root specimen provided in an embodiment of the present application.

[0054] In the drawings, the same reference numerals are used for the same components. The drawings are not drawn to scale.

[0055] Description of Figure Numbers:

[0056] 100, blade root specimen; 1, specimen body; 11, baffle; 12, pressure plate; 121, covering portion; 122, extension portion; 123, first layer; 124, second layer; 2, core body; 21, mandrel; 211, first section; 2111, threaded sleeve; 2112, insulating coating; 212, second section; 2121, plug connector; 22, support member; 23, separator; 3, connecting flange;

[0057] 200, mold; 201, assembly plane; 202, pad;

[0058] 300, test device; 301, test bench; 302, positioning seat;

[0059] X, first direction; Y, second direction; Z, third direction. DETAILED DESCRIPTION

[0060] The features and exemplary embodiments of various aspects of the present application will be described in detail below. In the detailed description below, many specific details are proposed to provide a comprehensive understanding of the present application. However, it is obvious to those skilled in the art that the present application can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present application by illustrating examples of the present application. In the accompanying drawings and the following description, at least some of the known structures and technologies are not shown to avoid unnecessary ambiguity in the present application; and, for clarity, the size of some structures may be exaggerated. In addition, the features, structures or characteristics described below may be combined in one or more embodiments in any suitable manner.

[0061] The directional words appearing in the following description are all directions shown in the figure, and do not limit the specific steps and structures of the blade root specimen and its manufacturing method of this application. In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "installation" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0062] It should be noted that the words first direction X, second direction Y and third direction Z recorded in this application are only used to more clearly describe the specific structure of this application in conjunction with the drawings, and this application is not limited thereto. Among them, the first direction X, the second direction Y and the third direction Z have an angle between each other. Optionally, the first direction X, the second direction Y and the third direction Z are perpendicular to each other.

[0063] like Figure 1 and Figure 2 As shown, the embodiment of the present application provides a blade root specimen 100, wherein the blade root specimen 100 includes a specimen body 1 and a core body 2; the core body 2 is arranged inside the specimen body 1, and the core body 2 includes at least one core shaft 21, the core shaft 21 is substantially in a long strip structure extending along a first direction X, and the core shaft 21 has a central axis extending along the first direction X;

[0064] Along the second direction Y and / or the third direction Z, the projection of the core shaft 21 is symmetrical along its central axis; the uniformity of the overall structure of the core shaft 21 can be effectively improved, and when subjected to external force, the force uniformity of various parts of the core shaft 21 can be improved, thereby improving the force uniformity of the core body 2 and the blade root sample 100 as a whole, effectively reducing the damage of the blade root sample 100 due to stress concentration when subjected to external force, and ensuring the normal progress of the test.

[0065] like Figure 1 and Figure 2As shown, according to one aspect of an embodiment of the present application, the sample body 1 also has a central axis extending along the first direction X; along the second direction Y, the projection of the central axis of the sample body 1 coincides with the projection of the central axis of the mandrel 21, and the projection of the sample body 1 is symmetrical along its central axis.

[0066] By making the sample body 1 symmetrical in structure, the uniformity of the overall structure of the sample body 1 can be effectively improved. When subjected to external force, the force uniformity of each part of the sample body 1 can be improved, thereby further improving the overall force uniformity of the blade root sample 100, further reducing the damage of the blade root sample 100 due to stress concentration when subjected to external force, and ensuring the normal progress of the test.

[0067] like Figure 2 As shown, according to one aspect of the embodiment of the present application, the core body 2 includes a plurality of mandrels 21, and the plurality of mandrels 21 are evenly spaced along the second direction Y; along the third direction Z, the projections of the mandrels 21 are symmetrically arranged along the central axis of the sample body 1. In this way, the uniformity of the overall structure of the core body 2 can be further improved, and the force uniformity of the blade root sample 100 can be improved to the greatest extent by combining the mandrels 21 and the sample body 1 with symmetrical structures, further reducing the damage of the blade root sample 100 due to stress concentration when subjected to external force, thereby ensuring the normal progress of the test.

[0068] In the figure, three core shafts 21 are used as an example to illustrate the blade root specimen 100. It should be noted that the number of core shafts 21 can be adjusted according to specific requirements of the test, and the present application is not limited thereto.

[0069] like Figure 1 and Figure 2 As shown, according to one aspect of the embodiment of the present application, the core shaft 21 includes a first section 211 and a second section 212 arranged along a first direction X, and the first section 211 and the second section 212 are detachably connected;

[0070] The first section 211 is a cylindrical structure. Along the direction away from the first section 211, the size of the second section 212 along the third direction Z gradually decreases and the size along the second direction Y gradually increases. The second section 212 can be regarded as a paddle-like structure. The cross-section of the end of the second section 212 connected to the first section 211 is roughly circular, and the cross-section of the end of the second section 212 away from the first section 211 is roughly long and narrow. Along the direction from one end of the second section 212 toward the first section 211 to the end of the second section 212 away from the first section 211, the second section 212 has a smooth deformation transition, so that the second section 212 has a flat surface.

[0071] like Figure 3As shown, according to one aspect of the embodiment of the present application, the first section 211 is a threaded sleeve 2111 which is hollow inside. The threaded sleeve 2111 is an internal hollow structure, and threads are formed on the inner and outer surfaces thereof.

[0072] An insulating coating layer 2112 is provided on the outer circumference of the threaded sleeve 2111 . The insulating coating layer 2112 is formed by insulating yarn being wound around the outer circumference of the threaded sleeve 2111 .

[0073] The outer surface of the threaded sleeve 2111 is first sandblasted to form a sandblasted layer, and then the insulating yarn is first wrapped and filled into the thread groove. After the insulating yarn filled in the thread groove is roughly flush with the top of the thread, at least two layers of insulating yarn are continued to be wrapped around the outer surface of the threaded sleeve 2111.

[0074] By providing the sandblasting layer and the insulating coating layer 2112 , the friction between the first section 211 and other components of the core 2 and / or the sample body 1 during assembly can be effectively improved to ensure the assembly reliability of the first section 211 .

[0075] Optionally, according to one aspect of the embodiment of the present application, the difference between the maximum distance and the minimum distance between the outer surface of the insulating coating 2112 and the axis of the threaded sleeve 2111 is less than or equal to 2 mm. This ensures that when the first section 211 is disposed inside the core 2, the fit between the periphery of the first section 211 and the core 2 is ensured, and the gap between the first section 211 and other parts of the core 2 and / or the sample body 1 due to the poor flatness of the outer surface is avoided, which affects the assembly reliability of the first section 211. This ensures that during the test of the blade root sample 100, after the first section 211 is installed on the test device 300, the first section 211 is not pulled out from the inside of the sample body 1 after being stressed, and ensures the normal conduct of the test.

[0076] like Figure 4 As shown, according to one aspect of the embodiment of the present application, the second section 212 is made of foam material, and the selected material can be polyester fiber, polyvinyl chloride or other materials. The second section 212 is formed with a plug connector 2121 at the end facing the first section 211, and the plug connector 2121 is plugged into the interior of the first section 211 in an interference fit manner to achieve a reliable connection between the two.

[0077] like Figure 5 As shown, according to one aspect of an embodiment of the present application, the core body 2 also includes a support member 22, and each core shaft 21 is provided with a support member 22 on both sides along the second direction Y, the support member 22 is fitted and connected with the corresponding core shaft 21, and the two side surfaces of the support member 22 along the third direction Z are respectively flush with the two side surfaces of the core shaft 21 along the third direction Z.

[0078] By providing the support member 22, the gaps between the mandrels 21 can be filled, thereby providing support and protection for the mandrels 21. It is understood that the surface of the support member 22 facing the mandrel 21 is concavely formed with a groove structure for a portion of the support member 22 to be embedded, so as to provide effective support for the mandrel 21.

[0079] like Figure 5 As shown, according to one aspect of an embodiment of the present application, the core body 2 also includes a partition 23, and a partition 23 is provided between every two adjacent core shafts 21. The two sides of the partition 23 along the second direction Y are respectively connected to the support members 22 connected to the two core shafts 21, and the two side surfaces of the partition 23 along the third direction Z are respectively flush with the two side surfaces of the core shaft 21 along the third direction Z. The partition 23 is used to evenly separate the core shafts 21 and provide support for the support members 22 located on both sides thereof.

[0080] Optionally, the materials of the partition 23 and the support member 22 can be the same, and the two can be fixedly connected, or the partition 23 and the support member 22 can be directly integrally formed.

[0081] Since the size of the second section 212 of the core shaft 21 along the third direction Z gradually decreases along the direction away from the first section 211, the portion of the partition 23 corresponding to the second section 212 of the core shaft 21 along the second direction Y and the portion of the support member 22 corresponding to the second section 212 of the core shaft 21 along the second direction Y gradually decreases in size along the direction from the first section 211 to the second section 212, so as to ensure that the two side surfaces of the partition 23 along the third direction Z, the two side surfaces of the support member 22 along the third direction Z and the two side surfaces of the core shaft 21 along the third direction Z can be spliced ​​to form a flat surface, so that the two side surfaces of the core body 2 along the third direction Z form a flat surface, which is beneficial to improving the close fit effect between the sample body 1 and the core body 2.

[0082] like Figure 5 As shown, according to one aspect of an embodiment of the present application, the sample body 1 includes two baffles 11 relatively arranged along the second direction Y and two pressure plates 12 relatively arranged along the third direction Z. The two baffles 11 and the two pressure plates 12 are alternately connected to enclose a cavity. The core 2 is arranged in the cavity, and the two side surfaces of the core 2 along the third direction Z are respectively connected to the two pressure plates 12, and the two side surfaces of the core 2 along the second direction Y are respectively connected to the two baffles 11.

[0083] According to one aspect of an embodiment of the present application, the pressure plate 12 includes a covering portion 121 and an extension portion 122 arranged and connected along a first direction X, the two covering portions 121 are respectively connected to the two sides of the core body 2 along a third direction Z, and the two extension portions 122 are stacked and connected along the third direction Z to cover the core body 2 therein, simulating the structure of an actual blade root pitch circle to improve the reference value of the test results.

[0084] Optionally, according to one aspect of the embodiment of the present application, the blade root specimen 100 further includes a connecting flange 3 for connecting with the test device 300 during the test process. The connecting flange 3 is connected to the end of the first section 211 of each mandrel 21 away from the second section 212 thereof, and the end of the first section 211 away from the second section 212 protrudes from an end surface of the specimen body 1 along the first direction X, so that after the connecting flange 3 is assembled, a gap is formed between the connecting flange 3 and the specimen body 1, so as to prevent the specimen body 1 from contacting with the flange during the subsequent test process and causing interference to the force of the blade root specimen 100.

[0085] like Figure 6 As shown, the blade root specimen 100 provided in the embodiment of the present application needs to be positioned on the test device 300 during testing. The test device 300 includes a test bench 301 and a positioning seat 302 disposed on the test bench 301. The blade root specimen 100 is detachably connected to the positioning seat 302 via a connecting flange 3 disposed at its end, and the covering portion 121 of the two stacked pressure plates 12 is clamped by a clamping member.

[0086] The dimension of the covering portion 121 along the first direction X is greater than or equal to 500 mm, so as to reserve sufficient clamping space during testing.

[0087] Specifically, the connecting flange 3 is connected to the positioning seat 302 by bolts, and the root static load and fatigue test are carried out according to the set test plan to verify the static load-bearing capacity and fatigue life of the embedded bolt sleeve of the blade root specimen 100, providing data support for the safety of the root connection.

[0088] The embodiment of the present application further provides a method for manufacturing a blade root sample 100, which can be used to manufacture the blade root sample 100 as described above. The method for manufacturing the blade root sample 100 includes:

[0089] The processing mandrel 21 is roughly in the shape of a long strip extending along the first direction X, so that the mandrel 21 extends along the first direction X, and the projections of the mandrel 21 along the second direction Y and / or the third direction Z are symmetrical along the central axis extending in the first direction X; the uniformity of the overall structure of the mandrel 21 can be effectively improved, and when subjected to external force, the uniformity of force at various locations of the mandrel 21 can be improved.

[0090] The core body 2 is manufactured so that the core body 2 includes at least one core shaft 21; the core body 2 is fixed inside the sample body 1 to form the blade root sample 100. While improving the uniformity of the overall structure of the core shaft 21, the uniformity of the force on the core body 2 and the blade root sample 100 as a whole is improved, effectively reducing the damage of the blade root sample 100 due to stress concentration when subjected to external force, and ensuring the normal progress of the test.

[0091] According to one aspect of the embodiment of the present application, the steps of processing the mandrel 21 so that the core 2 extends along the first direction X and the projections of the core 2 along the second direction Y and / or the third direction Z are symmetrical along the central axis extending in the first direction X specifically include:

[0092] Processing the first section 211, including:

[0093] A threaded sleeve 2111 is provided, and the outer surface of the threaded sleeve 2111 is sandblasted to form a sandblasted layer, and is stored in a dry environment;

[0094] Within 24 to 28 hours after the sandblasting layer is formed, the insulating yarn is wound on the outer circumference of the threaded sleeve 2111 to form an insulating coating layer 2112. Specifically, the insulating yarn is first wound to fill the thread groove. After the insulating yarn filled in the thread groove is roughly flush with the top of the thread, at least two layers of insulating yarn are continuously wound on the outer surface of the threaded sleeve 2111 to ensure that the outer surface of the threaded sleeve 2111 is completely covered.

[0095] The insulating yarn may be, for example, a glass fiber yarn with a size of 2400tex, and the terminal end of the insulating yarn is bonded and fixed by a glass fiber tape.

[0096] Processing the second section 212 includes:

[0097] A solid columnar structure is made of foam material. Along the direction away from the first section 211, the size of the second section 212 along the third direction Z gradually decreases and the size along the second direction Y gradually increases, so that the second section 212 roughly forms a paddle-shaped structure. Specifically, the cross section of the end of the second section 212 connected to the first section 211 is roughly circular, and the cross section of the end of the second section 212 away from the first section 211 is roughly long and narrow. Along the smooth deformation transition from one end of the second section 212 toward the first section 211 to the end of the second section 212 away from the first section 211, the second section 212 has a flat surface.

[0098] Connecting the first section 211 with the second section 212 includes:

[0099] The plug connector 2121 is formed in an integrally formed direction at the end of the second section 212 facing the first section 211 , and the plug connector 2121 is plugged into the interior of the first section 211 in an interference fit manner to ensure a reliable connection between the two.

[0100] According to one aspect of the embodiment of the present application, the step of manufacturing the core body 2 so that the core body 2 includes at least one mandrel 21 specifically includes:

[0101] A plurality of mandrels 21 are arranged so as to be evenly spaced along the second direction Y. The number of mandrels 21 can be flexibly adjusted according to actual needs.

[0102] Support members 22 are respectively connected to both sides of each core shaft 21 along the second direction Y, and the surface of the support member 22 facing the corresponding core shaft 21 is completely fitted with the outer surface of the core shaft 21. It can be understood that the surface of the support member 22 facing the core shaft 21 is recessed to form a groove structure for a part of the support member 22 to be embedded, so as to provide effective support for the core shaft 21; the two side surfaces of the support member 22 along the third direction Z are respectively flush with the two side surfaces of the core shaft 21 along the third direction Z, and the core shaft 21 and the support member 22 are matched to form a flat surface in the third direction Z, so as to ensure that the two side surfaces of the core body 2 along the third direction Z can be in close contact with the inner surface of the cavity of the sample body 1 in the subsequent process.

[0103] A separator 23 is provided between every two adjacent mandrels 21, and the two sides of the separator 23 along the second direction Y are respectively connected to the support members 22 connected to the two mandrels 21, and the two side surfaces of the separator 23 along the third direction Z are respectively flush with the two side surfaces of the mandrel 21 along the third direction Z. The separator 23 is used to evenly separate the mandrels 21, and at the same time provide support for the support members 22 located on both sides thereof, so as to further enhance the effective support of the support members 22 to each mandrel 21. Optionally, the separator 23 and the support member 22 can be made of the same material, and the two can be fixedly connected, or the separator 23 and the support member 22 can be directly integrally formed.

[0104] like Figure 7 As shown, according to one aspect of the embodiment of the present application, the step of fixing the core 2 inside the sample body 1 specifically includes:

[0105] A mold 200 is set up, and the mold 200 has an assembly plane 201. A pad 202 is laid on the assembly plane 201. The surface of the pad 202 on one side facing away from the assembly plane 201 can be in contact with the surface of the second section 212 of the core shaft 21 along the third direction Z; that is, the surface of the pad 202 on one side facing away from the assembly plane 201 is adapted to the surface of the second section 212 of the core shaft 21 along the third direction Z.

[0106] Laying the first layer 123, so that a portion of the first layer 123 is laid on the assembly plane 201, and another portion of the first layer 123 is laid on the backing plate 202, so that the portion of the first layer 123 laid on the backing plate 202 forms a shape that matches the surface of the second section 212 of the mandrel 21 along the third direction Z;

[0107] The core body 2 is arranged on the first layer 123 so that the first section 211 of each mandrel 21 is correspondingly fitted with the portion of the first layer 123 laid on the assembly plane 201, and the second section 212 of each mandrel 21 is correspondingly fitted with the portion of the first layer 123 laid on the pad 202, so that the surface of the core body 2 facing the first layer 123 is tightly fitted with the first layer 123.

[0108] Baffles 11 are respectively arranged on both sides of the core 2 along the second direction Y, so that the baffles 11 are in contact with the first ply 123; a second ply 124 is laid on the side of the core 2 and the two baffles 11 away from the first ply 123, and the second ply 124 is respectively in contact with the core 2 and the two baffles 11.

[0109] Adhesive liquid is injected into the cavity enclosed by the first ply 123 , the second ply 124 and the two baffles 11 . After the adhesive liquid solidifies, the first ply 123 and the second ply 124 form two pressing plates 12 and two baffles 11 , which are combined to form the sample body 1 .

[0110] The bonding liquid is a liquid resin, which after solidification bonds and fixes the core 2 , the two baffles 11 , the first layer 123 and the second layer 124 .

[0111] When laying the first layer 123 and the second layer 124, it is necessary to ensure that the first layer 123 and the second layer 124 are tightly fitted to the core body 2, and ensure that the first layer 123 and the second layer 124 have a spacing of less than or equal to 5 mm from the end of the first section 211 of the core shaft 21 away from the second section 212, so that after the first layer 123 and the second layer 124 form the pressure plate 12, a spacing of less than or equal to 5 mm is formed between the connecting flange 3.

[0112] The dimension of the portion where the first ply 123 and the second ply 124 are bonded together along the first direction X is greater than or equal to 500 mm, so as to reserve a clamping space during testing.

[0113] The portions of the first ply 123 and the second ply 124 protruding from the two baffles 11 along the second direction Y are cut to form a complete blade root specimen 100 .

[0114] The embodiment of the present application provides a blade root manufacturing method, which can effectively improve the uniformity of the overall structure of the core shaft 21 by making the core shaft 21 arranged inside the core body 2 present a symmetrical structure along the second direction Y and / or the third direction Z. Therefore, when subjected to external force, the force uniformity of the core shaft 21, the core body 2 and the blade root specimen 100 as a whole is improved, and the damage of the blade root specimen 100 due to stress concentration when subjected to external force is effectively reduced, thereby ensuring the normal progress of the test.

[0115] Although the present application has been described with reference to preferred embodiments, various modifications may be made thereto and parts thereof may be replaced with equivalents without departing from the scope of the present application. In particular, the various technical features mentioned in the various embodiments may be combined in any manner as long as there are no structural conflicts. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A blade root specimen (100), characterized in that: The blade root sample (100) comprises: Sample body (1); A core (2) is arranged inside the sample body (1), wherein the core (2) comprises at least one core shaft (21), wherein the core shaft (21) has a central axis extending along a first direction (X); Along the second direction (Y) and / or the third direction (Z), the projection of the core shaft (21) is symmetrical along its central axis; The first direction (X), the second direction (Y) and the third direction (Z) have angles therebetween.

2. The blade root specimen (100) according to claim 1, characterized in that The sample body (1) has a central axis extending along the first direction (X); along the second direction (Y), the projection of the central axis of the sample body (1) coincides with the projection of the central axis of the mandrel (21), and the projection of the sample body (1) is symmetrical along its central axis.

3. The blade root specimen (100) according to claim 2, characterized in that The core body (2) comprises a plurality of core shafts (21), and the plurality of core shafts (21) are evenly spaced and arranged along the second direction (Y); Along the third direction (Z), the projection of the core axis (21) is symmetrically arranged along the central axis of the sample body (1).

4. The blade root specimen (100) according to claim 3, characterized in that The core shaft (21) comprises a first section (211) and a second section (212) arranged along a first direction (X), and the first section (211) and the second section (212) are detachably connected; The first section (211) is a cylindrical structure, and along the direction away from the first section (211), the size of the second section (212) along the third direction (Z) gradually decreases and the size along the second direction (Y) gradually increases.

5. The blade root specimen (100) according to claim 4, characterized in that The first section (211) is a threaded sleeve (2111) with a hollow interior. An insulating coating layer (2112) is provided on the outer circumference of the threaded sleeve (2111). The insulating coating layer (2112) is formed by insulating yarn wound around the outer circumference of the threaded sleeve (2111).

6. The blade root specimen (100) according to claim 5, characterized in that The difference between the maximum distance and the minimum distance between the outer surface of the insulating coating (2112) and the axis of the threaded sleeve (2111) is less than or equal to 2 mm.

7. The blade root specimen (100) according to claim 4, characterized in that The second section (212) is a solid structure made of foam material; a plug connector (2121) is formed at the end of the second section (212) facing the first section (211), and the plug connector (2121) is plugged into the interior of the first section (211).

8. The blade root specimen (100) according to claim 1, characterized in that The core body (2) further comprises a support member (22), each of the core shafts (21) being provided with the support member (22) on both sides along the second direction (Y), the support member (22) being fitted and connected to the corresponding core shaft (21), and the two side surfaces of the support member (22) along the third direction (Z) are respectively flush with the two side surfaces of the core shaft (21) along the third direction (Z).

9. The blade root specimen (100) according to claim 8, characterized in that The core body (2) further comprises a separator (23), wherein the separator (23) is provided between every two adjacent core shafts (21), and the two sides of the separator (23) along the second direction (Y) are respectively connected to the support members (22) connected to the two core shafts (21), and the two side surfaces of the separator (23) along the third direction (Z) are respectively flush with the two side surfaces of the core shaft (21) along the third direction (Z).

10. The blade root specimen (100) according to claim 1, characterized in that The sample body (1) comprises two baffles (11) arranged opposite to each other along the second direction (Y) and two pressing plates (12) arranged opposite to each other along the third direction (Z); the two baffles (11) and the two pressing plates (12) are alternately connected to enclose a cavity; the core (2) is in the cavity, and the two side surfaces of the core (2) along the third direction (Z) are respectively connected to the two pressing plates (12); the two side surfaces of the core (2) along the second direction (Y) are respectively connected to the two baffles (11).

11. The blade root specimen (100) according to claim 10, characterized in that The pressing plate (12) comprises a covering portion (121) and an extending portion (122) arranged and connected along the first direction (X), the two covering portions (121) are respectively connected to two sides of the core (2) along the third direction (Z), and the two extending portions (122) are stacked and connected along the third direction (Z).

12. The blade root specimen (100) according to claim 4, characterized in that An end portion of the first section (211) away from the second section (212) protrudes from an end surface of the sample body (1) along the first direction (X).

13. A method for manufacturing a blade root specimen (100), characterized in that: The blade root sample (100) can be used to manufacture the blade root sample (100) according to any one of claims 1 to 12, wherein the manufacturing method of the blade root sample (100) comprises: Processing the mandrel (21) so that the mandrel (21) extends along a first direction (X), and the projections of the mandrel (21) along a second direction (Y) and / or a third direction (Z) are symmetrical along a central axis extending in the first direction (X); Manufacturing a core body (2), so that the core body (2) includes at least one core shaft (21); The core (2) is fixed inside the sample body (1).

14. The method for manufacturing a blade root specimen (100) according to claim 13, characterized in that: Processing the mandrel (21) so that the core (2) extends along a first direction (X), and the projections of the core (2) along a second direction (Y) and / or a third direction (Z) are symmetrical along a central axis extending in the first direction (X), comprising: The first processing stage (211) comprises: A threaded sleeve (2111) is provided; Winding insulating yarn on the outer circumference of the threaded sleeve (2111) to form an insulating coating layer (2112); Processing the second stage (212) includes: A solid columnar structure is made of foam material, and along a direction away from the first section (211), the size of the second section (212) along the third direction (Z) gradually decreases and the size along the second direction (Y) gradually increases; Connecting the first section (211) and the second section (212) comprises: A plug connector (2121) is formed at the end of the second section (212) facing the first section (211), and the plug connector (2121) is plugged into the interior of the first section (211).

15. The method for manufacturing a blade root specimen (100) according to claim 13, characterized in that: Manufacturing a core body (2) so that the core body (2) includes at least one mandrel (21), comprising: Arranging a plurality of the mandrels (21), so that the plurality of mandrels (21) are evenly spaced along the second direction (Y); Support members (22) are respectively connected and arranged on both sides of each core shaft (21) along the second direction (Y), so that the two side surfaces of the support member (22) along the third direction (Z) are respectively flush with the two side surfaces of the core shaft (21) along the third direction (Z); A separator (23) is arranged between every two adjacent core shafts (21), and the two sides of the separator (23) along the second direction (Y) are respectively connected to the support members (22) connected to the two core shafts (21), and the two side surfaces of the separator along the third direction (Z) are respectively flush with the two side surfaces of the core shaft (21) along the third direction (Z).

16. The method for manufacturing a blade root specimen (100) according to claim 13, characterized in that: The core (2) is fixed inside the sample body (1), comprising: An assembly plane (201) is set, and a pad (202) is laid on the assembly plane (201), wherein a surface of the pad (202) facing away from the assembly plane (201) can be in contact with a surface of the second section (212) of the mandrel (21) along a third direction (Z); Laying a first layer (123) so that a portion of the first layer (123) is laid on the assembly plane and another portion of the first layer (123) is laid on the backing plate (202); A core body (2) is arranged on the first layer (123), so that the first section (211) of each mandrel (21) is correspondingly fitted with the portion of the first layer (123) laid on the assembly plane, and the second section (212) of each mandrel (21) is correspondingly fitted with the portion of the first layer (123) laid on the pad (202); baffles (11) are respectively arranged on both sides of the core (2) along the second direction (Y), so that the baffles (11) are in close contact with the first ply (123); Laying a second layer (124) on the side of the core (2) and the two baffles (11) away from the first layer (123), and making the second layer (124) fit closely with the core (2) and the two baffles (11) respectively; Injecting adhesive liquid into a cavity enclosed by the first ply (123), the second ply (124) and the two baffles (11); When the adhesive liquid solidifies, the first layer (123) and the second layer (124) form two pressing plates (12).

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