A tower model with dynamically adjustable stiffness distribution and mass distribution and a method of operation thereof

Abstract

The application discloses a tower model with dynamically adjustable rigidity distribution and mass distribution and a working method thereof, and belongs to the field of offshore wind power generation. The tower model comprises an inner tower, an outer tower, an aluminum rod and an attached dynamic support device. The inner tower, the inner aluminum rod and the attached dynamic support device change the transmission direction of the force borne by the tower by changing the extension length of the support rod, thereby changing the rigidity distribution of the tower along the height direction without destroying the existing model, so that the rigidity distribution of the model is similar to that of the prototype, the first-order vibration frequency of the tower is consistent with the theoretical value, and the Froude similarity system is satisfied. The mass block on the inner tower aluminum rod can move along the height direction of the aluminum rod, so that the mass distribution of the model is similar to that of the prototype, thereby ensuring that the center of mass position of the model and the center of mass position of the prototype fully satisfy the Froude similarity system. The application reduces the test error caused by the model itself, and finally can fully ensure the accuracy of the model test.

Description

Technical Field

[0001] This invention belongs to the field of offshore wind power generation, specifically relating to a tower model for physical model testing of a water tank on an offshore wind power platform and its working method. Background Technology

[0002] Offshore floating wind power technology, as an important marine renewable energy development technology, has received widespread attention in recent years. Compared with onshore wind power, offshore wind power has advantages such as stable resources and less land occupation. However, because the relevant technologies of offshore wind power are still not mature enough, it is necessary to verify the relevant floating wind turbine structures through pool tests. At present, most pool tests are based on the design of wind turbine models and model tests based on the Froude similarity system; however, in the actual test process, model making, especially the tower model making, often presents many difficulties. First, the tower stiffness of actual floating wind turbines varies along the height direction. It is difficult to realize this variable stiffness design in the actual model making process, resulting in a large discrepancy between the stiffness distribution of the model along the height direction and the theoretical value obtained by converting the prototype under the Froude similarity system. This may lead to a large difference between the first-order vibration frequency of the tower and the theoretical value, which does not meet the Froude similarity system. For example, Chinese Patent Publication No. 202410716939.1 discloses a scaled-down model of a variable stiffness floating wind turbine tower and its stiffness adjustment method. Secondly, due to errors in model making and assembly, the actual model's center of gravity often inevitably deviates from the theoretical value calculated from the prototype under the Froude similarity system. If these problems exist after the tower is manufactured and does not meet the experimental requirements, it cannot be modified; otherwise, the experimental model will be destroyed. Summary of the Invention

[0003] (a) The technical problem solved by the present invention is:

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a tower model with dynamically adjustable stiffness and mass distribution. This tower model allows for adjustment of both the stiffness and mass distribution along the height direction within a certain range, as well as the mass distribution along the height direction within a certain range. This minimizes the differences in stiffness and mass distribution between the model and the prototype within the Froude similarity system and their resulting impact.

[0005] (b) To achieve the above objectives, the technical solution of the present invention is as follows:

[0006] A tower model with dynamically adjustable stiffness and mass distribution includes a conical inner tower 1 with a closed first end 101 and an open second end 102, and an outer tower 4 fitted onto the outer wall of the inner tower 1, having a geometrically similar shape to the inner tower. The size of the first end 101 of the inner tower is larger than the size of the second end 102. The outer end face of the first end 101 is connected to a first flange 301, which is fixed to a six-component force sensor 7 at the bottom of the tower. The inner end face of the first end 101 has a threaded hole. The inner wall of the second end 102 is threaded, and the second end 102 is fixed to an inner tower cover plate 8 via a threaded connection. The inner tower cover plate 8 is a circular cover plate with a diameter matching the inner diameter of the second end 102, effectively closing the second end 102. An aluminum rod 2 is installed inside the inner tower 1, with its first end 201 fixed... A second flange 302 is fixed and bolted to the threaded hole on the inner end face of the first end 101 of the inner tower. A third flange 303 is fixed to the second end 202 of the aluminum rod and bolted to the inner end face of the inner tower cover plate 8. The aluminum rod 2 is provided with external threads, and several mass blocks 6 are arranged along the height direction of the aluminum rod 2. The mass blocks 6 are annular and have threads on their inner walls that engage with the threads of the aluminum rod 2. The mass blocks 6 move along the height direction of the aluminum rod 2 through the threads. The aluminum rod 2 is arranged with multiple sets of dynamic support adjustment devices 5 along the height direction. Each set of dynamic support adjustment devices 5 includes a base 505, multiple remote-controlled wireless servo motors 501, the same number of aluminum telescopic support rods 502 controlled by the remote-controlled wireless servo motors 501, a buffer 503, and a flexible rubber contact head 504. Each remote-controlled wireless servo motor 501 individually controls a telescopic support rod 502; the dynamic support adjustment device 5 is connected to the aluminum rod 2 via a thread on the base 505, and can spirally rise or fall along the height direction of the aluminum rod 2. Each remote-controlled wireless servo motor 501 is fixed on the base 505. The telescopic support rod 502 is divided into two sections. The beginning of the first section is connected to the output shaft of the remote-controlled wireless servo motor 501, and the end is connected to one end of the buffer 503; the beginning of the second section of the telescopic support rod 502 is connected to the other end of the buffer 503, and a flexible rubber contact head 504 is installed at the end. The flexible rubber contact head 504 has no sliding support with the inner wall of the inner tower cylinder 1.

[0007] Furthermore, the outer tower 4 is connected to the inner tower 1 by adhesive bonding.

[0008] Furthermore, the buffer 503 is a common miniature cylindrical hydraulic buffer, which can be connected to the telescopic support rod 502 via welding, pre-drilled threads and bolt holes, and pre-drilled pins. Preferably, one end of the buffer 503 is connected and fixed to the telescopic support rod 502 near the aluminum rod 2 via pre-drilled threads and bolt holes, and the other end is connected and fixed to the telescopic support rod 502 near the inner tower wall via a pin. A schematic diagram of the connection via pre-drilled threads and bolt holes can be found in [reference needed]. Figure 7 For a diagram showing the connection via a pre-reserved pin, please refer to section 10.

[0009] Furthermore, the non-slip support means that when the tower is subjected to external loads and undergoes small deformation, the flexible rubber contact head 504 can undergo appropriate deformation, thereby ensuring that the contact point with the inner tower 1 does not change significantly.

[0010] Furthermore, the inner tower cylinder is made of aluminum alloy, and the material of the outer tower cylinder must meet the following requirements:

[0011] (1) Easy to process;

[0012] (2) Lightweight, allowing for a large range of weight adjustments;

[0013] (3) The stiffness is small, which has little impact on the stiffness control of the inner tower tube. The stiffness of the tower tube model is approximately equal to the stiffness of the inner tower tube.

[0014] The outer tower is preferably made of polystyrene foam.

[0015] Furthermore, the total mass of the outer tower, inner tower, internal aluminum rod, and their auxiliary devices meets the mass similarity requirements under the Froude similarity system. The auxiliary devices refer to all devices connected to the aluminum rod, including several dynamic support adjustment devices and several mass blocks. The inner tower, internal aluminum rod, and their auxiliary devices ensure similar stiffness, thereby guaranteeing the reliability of the dynamic response transmission of the upper structure of the wind turbine. Based on this, the outer tower fully ensures geometric similarity to guarantee sufficient similarity of aerodynamic loads. The similarity of aerodynamic loads is achieved through the dimensionless aerodynamic load C. F To ensure this, the specific equation is as follows:

[0016]

[0017] Where: F(z) is the aerodynamic load at height z; ρ is the fluid density; V is the fluid velocity; C D (z) is the local drag coefficient at height Z (dimensionless); D is the local diameter of the tower; V REF D represents the wind speed at the top of the tower. REF The diameter is the top diameter of the tower.

[0018] The equation for mass similarity is specifically as follows:

[0019]

[0020] Where: m p The total mass of the prototype floating wind turbine tower is m m Let λ be the total mass of the model tower, and λ be the scale used in the model test under the Froude similarity system.

[0021] The equation for geometric similarity is specifically:

[0022]

[0023] Where: Lp represents the geometric feature length of the prototype floating wind turbine tower, Lm represents the geometric feature length of the model tower, and λ is the scale used in the model test under the Froude similarity system.

[0024] Furthermore, the present invention provides a working method for a tower model with dynamically adjustable stiffness and mass distribution, the installation steps of which are as follows: (1) The second flange 302 of the first end 201 of the aluminum rod is pre-fixed to the first end 101 of the inner tower, while the second end 202 of the aluminum rod is not connected to the second end 102 of the inner tower. (2) The mass block 6 is appropriately adjusted so that the mass distribution of the model tower along the height direction is close to that of the prototype tower, ensuring that the center of mass of the model tower and the center of mass of the prototype tower satisfy the Froude similarity system. (3) The third flange 303 of the second end 202 of the aluminum rod is fixed to the second end 102 of the inner tower. (4) The remote-controlled wireless servo motor 501 is controlled and adjusted, and the extension length of the telescopic support rod 502 is adjusted to make full contact with the inner wall of the inner tower 1, ensuring that the stiffness distribution of the model tower along the height direction is similar to that of the prototype tower. (5) The first flange 301 of the first end 101 of the inner tower is fixed to the six-component force sensor 7 at the bottom of the model tower, so as to realize the installation of the tower model that can dynamically adjust the stiffness distribution and mass distribution.

[0025] Furthermore, the tower was tested according to the following steps:

[0026] Step 1: First, ensure that all components of the tower model that meet the requirements of dynamically adjustable stiffness and mass distribution can be assembled as required and can start normally.

[0027] Step 2: According to the actual test requirements, install the tower model onto the floating platform for the test and connect it with other parts of the wind turbine. At the same time, input the wind field and wave field required for the test into the test pool.

[0028] Step 3: Collect relevant data using the six-component force sensor at the bottom of the model tower.

[0029] Step 4: Change the required wind field and wave field according to the test requirements, and repeat step 3.

[0030] The principle of this invention is as follows:

[0031] By adopting a strategy of separate similarities and overall combination, the entire tower is divided into two parts: an inner tower and an outer tower. For the inner tower, the internal aluminum rods and their auxiliary devices are dynamically supported. By appropriately changing the extension length of the support rods, the direction of force transmission on the tower is changed, thereby changing the stiffness distribution of the tower along the height direction. Ultimately, this allows it to have a similar stiffness distribution to the prototype, thus ensuring stiffness similarity and providing a basis for mass similarity, rather than forcibly requiring it to meet geometric similarity. For any missing mass or geometric similarity, the outer tower is used to compensate for and ensure it.

[0032] (c) The beneficial effects of the present invention are as follows:

[0033] Compared with existing technologies, this invention has the following advantages: It is adaptable to water tank tests of various floating wind turbines. The polystyrene foam outer tower overcomes the previous difficulties in processing the tower's shape, allowing for high-precision replication of the original tower's geometry. Simultaneously, its ease of processing also meets the manufacturing needs of various irregularly shaped towers. The inner tower, its internal aluminum rods, and its associated dynamic support device can change the direction of force transmission by altering the extension length of the support rods, thereby changing the stiffness distribution along the height of the tower without damaging the existing model. This ensures that the model's stiffness distribution is similar to the prototype's height, guaranteeing that the tower's first-order vibration frequency matches the theoretical value and satisfies the Froude similarity system. The mass block on the aluminum rod of the inner tower can move along the height of the aluminum rod, achieving a mass distribution similar to the prototype's height, thus ensuring that the model's center of mass position fully satisfies the Froude similarity system. Through these methods, experimental errors caused by the model itself are significantly reduced, ultimately ensuring the accuracy of the model test. Attached Figure Description

[0034] Figure 1 This is a perspective view of the present invention;

[0035] Figure 2 The diagram shows a dynamic support device, where (a) the support rod is retracted and the dynamic support device is in an unsupported state, and (b) the support rod is extended and the dynamic support device is in a supported state.

[0036] Figure 3 This is a schematic diagram of the dynamic support device layout;

[0037] Figure 4 This is a three-dimensional layout diagram of the dynamic support device;

[0038] Figure 5 This is a cross-sectional view of the present invention;

[0039] Figure 6 This is a partial view of the present invention.

[0040] Figure 7 A schematic diagram showing the connection between the buffer and the support rod using threaded bolts.

[0041] Figure 8 Schematic diagram of an aluminum rod;

[0042] Figure 9 This is a schematic diagram of the mass block;

[0043] Figure 10 This is a schematic diagram showing the connection between the buffer and the support rod via a pin.

[0044] In the diagram: 1 Inner tower, 101 First end of inner tower, 102 Second end of inner tower, 2 Aluminum rod, 201 First end of aluminum rod, 202 Second end of aluminum rod, 301 First flange, 302 Second flange, 303 Third flange, 4 Outer tower, 401 Large end of outer tower, 402 Small end of outer tower, 5 Dynamic support adjustment device, 501 Remote-controlled wireless servo motor, 502 Telescopic support rod, 503 Buffer, 504 Flexible rubber contact head, 505 Base, 6 Mass block, 7 Six-component force sensor, 8 Inner tower cover plate. Detailed Implementation

[0045] The present invention will be further described in detail below with reference to specific embodiments, but the scope of the present invention is by no means limited to the following examples:

[0046] Specific implementation methods:

[0047] To make the above features and advantages of the present invention more apparent and understandable, specific embodiments are described below in conjunction with the accompanying drawings for detailed explanation.

[0048] A tower model with dynamically adjustable stiffness and mass distribution includes a conical inner tower 1 with a closed first end 101 and an open second end 102, and an outer tower 4 fitted onto the outer wall of the inner tower 1 with a geometrically similar shape to the inner tower. The dimension of the first end 101 of the inner tower is larger than the dimension of the second end 102, and the inner tower 1 is a conical tower. The outer end face of the first end 101 of the inner tower is connected to a first flange 301, which has a threaded hole. The first flange 301 is bolted to the six-component force sensor 7 at the bottom of the tower. The inner end face of the first end 101 of the inner tower is provided with a threaded hole, and the inner wall of the second end 102 of the inner tower is provided with threads. The second end 102 of the inner tower is threaded to the inner tower cover plate 8. The inner tower cover plate 8 is a circular cover plate with a diameter consistent with the inner diameter of the inner tower, which can close the second end 102 of the inner tower. The outer tower 4 includes a large end 401 and a small end 402. The outer tower 4 is connected to the inner tower 1 by adhesive. The inner tower 1 is equipped with an aluminum rod 2. A second flange 302 is welded to the first end 201 of the aluminum rod. The second flange 302 is bolted to the threaded hole on the inner end face of the first end 101 of the inner tower. A third flange 303 is welded to the second end 202 of the aluminum rod. The third flange 303 is bolted to the inner end face of the inner tower cover plate 8. The aluminum rod 2 has external threads, and several mass blocks 6 are arranged along the height of the aluminum rod. The mass blocks 6 are annular, and their inner walls are provided with features that connect to the aluminum rod 2. The threads interlock, and the mass block 6 moves along the height direction of the aluminum rod 2 via the threads. Multiple sets of dynamic support adjustment devices 5 are arranged along the height direction of the aluminum rod 2. Each set of dynamic support adjustment devices 5 includes a base 505, multiple remote-controlled wireless servo motors 501, an equal number of aluminum telescopic support rods 502 controlled by the remote-controlled wireless servo motors 501, a buffer 503, and a flexible rubber contact head 504. Each remote-controlled wireless servo motor 501 individually controls one telescopic support rod 502. The dynamic support adjustment device 5 is connected to the aluminum rod 2 via threads on the base 505 and can spirally rise or fall along the height direction of the aluminum rod 2 via the threads. Each remote-controlled wireless servo motor 501 is fixed on the base 505. The telescopic support rod 502 is divided into two sections. The first section's beginning is connected to the output shaft of the remote-controlled wireless servo motor 501, and its end is connected to one end of the buffer 503. The second section's beginning is connected to the other end of the buffer 503, and its end is equipped with a flexible rubber contact head 504. The flexible rubber contact head 504 has no sliding support against the inner wall of the inner tower cylinder 1. The buffer 503 is a common miniature cylindrical hydraulic buffer, which can be connected to the support rod 502 by welding, pre-drilled threads and bolt holes, or pre-drilled pins.Preferably, one end of the buffer 503 is connected and fixed to the telescopic support rod 502 near the aluminum rod 2 via a pre-drilled thread and bolt hole, and the other end is connected and fixed to the telescopic support rod 502 near the inner tower wall via a pin. A schematic diagram of the connection via the pre-drilled thread and bolt hole can be found in the attached diagram. Figure 7 For a schematic diagram of the connection via a pre-reserved pin, please refer to 10. The non-slip support refers to the flexible rubber contact head 504 undergoing appropriate deformation under external loads, ensuring that the contact point with the inner tower 1 does not change significantly. The buffer is a common miniature cylindrical hydraulic buffer, such as the ACE brand miniature buffer.

[0049] To facilitate connection, the inner tower 1 is a thin and straight aluminum alloy tube, and its first end is fixed to the first flange 301 by adhesive welding or thread connection; the outer tower 2 is made of polystyrene foam material.

[0050] To meet the experimental requirements, the total mass of the inner tower, aluminum rod and its auxiliary devices, and outer tower meets the mass similarity requirement. The auxiliary devices refer to all devices connected to the aluminum rod, including several dynamic support adjustment devices and several mass blocks. The mass similarity requirement means that the total mass of the three components meets the theoretical mass value obtained by converting the actual mass of the offshore floating wind turbine tower under the Froude similarity system. The mass distribution of the model along the height direction is adjusted by changing the position of the mass blocks through the aluminum rod and its auxiliary movable mass blocks, thereby ensuring that the position of the model's center of mass meets the Froude similarity system. The inner tower control ensures stiffness similarity under the Froude similarity system. By changing the extension length of the support rod through the aluminum rod and its auxiliary dynamic support devices, the direction of force transmission on the model tower is changed, thereby changing the stiffness distribution of the model tower along the height direction. This makes the stiffness distribution of the model similar to the prototype height, thus fully ensuring stiffness similarity under the Froude similarity system and ensuring the reliability of the dynamic response transmission of the wind turbine's upper structure. The outer tower, based on the inner tower, fully ensures geometric similarity to ensure sufficient similarity of aerodynamic loads.

[0051] The aforementioned mass similarity refers to the model's total mass satisfying the theoretical value obtained by converting the actual mass of the offshore floating wind turbine tower under the Froude similarity system. The specific mass similarity equation is as follows:

[0052]

[0053] Where: m p The total mass of the prototype floating wind turbine tower is m m Let λ be the total mass of the model tower, and λ be the scale used in the model test under the Froude similarity system.

[0054] The centroid position satisfying the Froude similarity system means that the model's centroid position satisfies the actual centroid position of the offshore floating wind turbine tower, which is the theoretical value obtained by converting it under the Froude similarity system. The specific conversion equation is as follows:

[0055]

[0056] Wherein: H p The height H of the center of mass of the prototype floating wind turbine tower from the bottom of the tower. m λ is the height of the centroid of the model tower from the bottom of the tower, and λ is the scale used in the model test under the Froude similarity system.

[0057] The control and guarantee of geometric similarity for the outer tower means that the geometric parameters of the outer tower are the theoretical values ​​of the model obtained by converting the actual geometric parameters of the offshore floating wind turbine tower under the Froude similarity system. The specific geometric similarity equations are as follows:

[0058]

[0059] Where: Lp represents the geometric feature length of the prototype floating wind turbine tower, Lm represents the geometric feature length of the model tower, and λ is the scale used in the model test under the Froude similarity system.

[0060] The control of the inner tower ensures stiffness similarity, meaning that the stiffness of the model tower and the prototype tower meet the Froude similarity system. The specific implementation method is as follows: (1) Strain gauges are attached to the outer surface of the model tower along the height direction and connected to a sensor acquisition device; (2) An external load is given in the actual test field, and the external load on the prototype tower meets the Froude similarity system; (3) The deformation distribution of the model tower along the height direction is measured and calculated by strain gauges, and compared with the deformation distribution of the prototype tower under its corresponding external load. It is determined whether the two meet the Froude similarity system. If they do not meet the requirements, the dynamic support device can be adjusted to change the local stiffness, thereby changing the local deformation, until the deformation of the model tower and the prototype tower meets the Froude similarity system. At this time, it can be considered that the stiffness of the two is similar.

[0061] In one embodiment, the main body of the inner tower is an aluminum alloy tube with an outer diameter of 48.6 mm; the main body of the outer tower is a polystyrene foam tube with an outer diameter of 120 mm at the large end and an outer diameter of 90.4 mm at the small end.

[0062] Furthermore, the present invention provides a working method for a tower model with dynamically adjustable stiffness and mass distribution, the installation steps of which are as follows: (1) The second flange 302 of the first end 201 of the aluminum rod is pre-fixed to the first end 101 of the inner tower, while the second end 202 of the aluminum rod is not connected to the second end 102 of the inner tower. (2) The mass block 6 is appropriately adjusted so that the mass distribution of the model tower along the height direction is close to that of the prototype tower, ensuring that the center of mass of the model tower and the center of mass of the prototype tower satisfy the Froude similarity system. (3) The third flange 303 of the second end 202 of the aluminum rod is fixed to the second end 102 of the inner tower. (4) The remote-controlled wireless servo motor 501 is controlled and adjusted, and the extension length of the telescopic support rod 502 is adjusted to make full contact with the inner wall of the inner tower 1, ensuring that the stiffness distribution of the model tower along the height direction is similar to that of the prototype tower. (5) The first flange 301 of the first end 101 of the inner tower is fixed to the six-component force sensor 7 at the bottom of the model tower, so as to realize the installation of the tower model that can dynamically adjust the stiffness distribution and mass distribution.

[0063] Furthermore, the tower was tested according to the following steps:

[0064] Step 1: First, ensure that all components of the tower model that meet the requirements of dynamically adjustable stiffness and mass distribution can be assembled as required and can start normally.

[0065] Step 2: According to the actual test requirements, install the tower model onto the floating platform for the test and connect it with other parts of the wind turbine. At the same time, input the wind field and wave field required for the test into the test pool.

[0066] Step 3: Collect relevant data using the six-component force sensor at the bottom of the model tower.

[0067] Step 4: Change the required wind field and wave field according to the test requirements, and repeat step 3.

Claims

1. A tower section model that can dynamically adjust stiffness distribution and mass distribution, characterized in that, The application relates to a conical inner tower cylinder (1) comprising a closed inner tower cylinder first end (101) and an open inner tower cylinder second end (102), and an outer tower cylinder (4) which is sleeved on the outer wall of the inner tower cylinder (1) and has a geometrically similar shape to the tower cylinder, wherein the size of the inner tower cylinder first end (101) is larger than the size of the inner tower cylinder second end (102); the outer end surface of the inner tower cylinder first end (101) is connected with a first flange plate (301), the first flange plate (301) is fixed with a six-component force sensor (7) at the tower bottom, and the inner end surface of the inner tower cylinder first end (101) is provided with a threaded hole; the inner wall of the inner tower cylinder second end (102) is provided with a thread, the inner tower cylinder second end (102) is fixed with an inner tower cylinder cover plate (8) through the thread, the inner tower cylinder cover plate (8) is a circular cover plate with a diameter consistent with the inner diameter of the inner tower cylinder second end (102) and capable of closing the inner tower cylinder second end (102); an aluminum rod (2) is arranged in the inner tower cylinder (1), the first end (201) of the aluminum rod is fixed with a second flange plate (302), the second flange plate (302) is fixed with the threaded hole in the inner end surface of the inner tower cylinder first end (101) through bolt connection, the second end (202) of the aluminum rod is fixed with a third flange plate (303), and the third flange plate (303) is connected with the inner end surface of the inner tower cylinder cover plate (8) through bolt connection; the aluminum rod (2) is provided with external threads, a plurality of mass blocks (6) are arranged along the height direction of the aluminum rod (2), the mass blocks (6) are circular rings, the inner wall of the mass blocks (6) is provided with threads matched with the threads of the aluminum rod (2), and the mass blocks (6) are moved along the height direction of the aluminum rod (2) through the threads; a plurality of groups of dynamic support adjusting devices (5) are arranged along the height direction of the aluminum rod (2), each group of dynamic support adjusting devices (5) comprises a base (505), a plurality of remote control type wireless servo motors (501), the same number of aluminum telescopic support rods (502) controlled by the remote control type wireless servo motors (501), a buffer (503) and a flexible rubber contact head (504); each remote control type wireless servo motor (501) controls one telescopic support rod (502); the dynamic support adjusting device (5) is connected with the aluminum rod (2) through the threads arranged on the base (505) and can ascend or descend in a spiral mode along the height direction of the aluminum rod (2) through the threads; each remote control type wireless servo motor (501) is fixed on the base (505), the telescopic support rod (502) is divided into two sections, the first section is connected with the output shaft of the remote control type wireless servo motor (501) at the starting end and connected with one end of the buffer (503) at the tail end; the starting end of the second section of the telescopic support rod (502) is connected with the other end of the buffer (503), the tail end is provided with one flexible rubber contact head (504), and the flexible rubber contact head (504) is supported without sliding with the inner wall of the inner tower cylinder (1); the mass distribution of the model along the height direction is adjusted by changing the positions of the mass blocks through the aluminum rod and the movable mass blocks attached to the aluminum rod, so that the mass center position of the model meets the Froude similarity system.The stiffness distribution of the model tower drum along the height direction can be changed by changing the transmission direction of the force suffered by the model tower drum through the aluminum rod and its attached dynamic support device, thereby changing the extension length of the support rod, so that the stiffness distribution of the model is similar to the prototype height, thereby fully ensuring the stiffness similarity under the Froude similarity system.

2. A dynamically adjustable stiffness and mass distribution tower section model according to claim 1, wherein, The outer tower cylinder (4) is connected with the inner tower cylinder (1) by means of adhesion.

3. A dynamically adjustable stiffness and mass distribution tower section model according to claim 1, wherein, One end of the buffer (503) is connected and fixed with the telescopic support rod (502) near one end of the aluminum rod (2) through reserved threads and bolt holes, and the other end is connected and fixed with the telescopic support rod (502) near the inner tower cylinder wall surface through a bolt.

4. The dynamically adjustable stiffness and mass distribution tower section model of claim 1, wherein, In the state of small deformation of the non-sliding support finger tower cylinder under external load, the flexible rubber contact head (504) can deform appropriately, so as to ensure that the contact point with the inner tower cylinder (1) does not change greatly.

5. A dynamically adjustable stiffness and mass distribution tower section model according to claim 1, wherein, The inner tower cylinder is made of aluminum alloy material, and the material of the outer tower cylinder is polystyrene foam material.

6. A dynamically adjustable stiffness and mass distribution tower section model according to claim 1, wherein, The total mass of the outer tower cylinder, the inner tower cylinder, the internal aluminum rod and the attached devices connected to the aluminum rod, including several dynamic support adjusting devices and several mass blocks, meets the mass similarity requirement in the Froude similarity system, and the inner tower cylinder, the internal aluminum rod and the attached devices ensure the rigidity similarity, thereby ensuring the reliability of the dynamic response transmission of the upper structure of the fan; on this basis, the outer tower cylinder fully ensures the geometric shape similarity, so as to ensure the full similarity of the aerodynamic load, and the similarity of the aerodynamic load is ensured by the dimensionless aerodynamic load ​ ， ； wherein: is the aerodynamic load at height z; is the fluid density; is the fluid flow rate; is the local drag coefficient at height Z; is the local diameter of the tower section; is the wind speed at the top of the tower section; is the diameter at the top of the tower section; The mass similarity equation is specifically: ； wherein: Mtot is the total mass of the prototype floating wind turbine tower, Mmod is the total mass of the model tower, L is the scale factor used in the model test under Froude similarity. The geometric similarity equation is specifically: ； wherein: Lp represents the characteristic geometric length of the prototype floating wind turbine tower, Lm represents the characteristic geometric length of the model tower, is the scale ratio used in the model test under the Froude similarity system.

7. A method of operating a tower model having dynamically adjustable stiffness and mass distributions as claimed in any one of claims 1 to 6, characterised in that, The steps are as follows: Step 1, first ensure that each component of the tower cylinder model capable of dynamically adjusting the stiffness distribution and mass distribution can be assembled as required and can be normally started; Step 2, according to the actual test requirements, install the tower cylinder model on the test floating platform, and connect it with other parts of the wind turbine, and input the required wind field and wave field in the test pool; Step 3, use the six-component force sensor at the bottom of the model tower cylinder to collect the corresponding data; Step 4, change the required wind field and wave field according to the test requirements, and repeat step 3.

8. The method of working according to claim 7, characterized in that, The installation steps of the tower cylinder model capable of dynamically adjusting the stiffness distribution and mass distribution are as follows: (1) the second flange plate (302) of the first end (201) of the aluminum rod is fixed with the first end (101) of the inner tower cylinder in advance, and the second end (202) of the aluminum rod is not connected with the second end (102) of the inner tower cylinder; (2) appropriately adjust the mass block (6) to make the mass distribution of the model tower cylinder along the height direction close to that of the prototype tower cylinder, and ensure that the mass center position of the model tower cylinder and the mass center position of the prototype tower cylinder meet the Froude similarity system; (3) the third flange plate (303) of the second end (202) of the aluminum rod is fixed with the second end (102) of the inner tower cylinder; (4) control and adjust the remote wireless servo motor (501) to fully contact the inner wall of the inner tower cylinder (1) by adjusting the extension length of the telescopic support rod (502), so as to ensure that the stiffness distribution of the model tower cylinder along the height direction is similar to that of the prototype tower cylinder; (5) the first flange plate (301) of the first end (101) of the inner tower cylinder is fixed with the six-component force sensor (7) at the bottom of the model tower cylinder, so as to realize the installation of the tower cylinder model capable of dynamically adjusting the stiffness distribution and mass distribution.

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