Wind tunnel-pool combined loading distributed hybrid test method for floating wind turbine

Abstract

The application discloses a kind of wind tunnel-pool combined loading's floating wind turbine distributed hybrid test method, establishes floating wind turbine multi-body / multi-physical field collaborative scale criterion, and floating wind turbine is divided into two independent physical models and numerical model and placed in different laboratories;Integrate physical model, numerical model, loading system and measuring system, build floating wind turbine physical-numerical distributed hybrid test platform;Data interaction and closed-loop control of physical-numerical hybrid test platform.The application uses wind turbine and floating platform as two relatively independent test substructures, different similarity criteria and geometric scale ratio are established, and different laboratories can be tested and loaded or computer simulated, and the technical problems of high-precision simulation and dynamic coupling response of environmental load in scale model test are solved through network data interaction collaborative online test and aerodynamic-hydrodynamic load loading under the coupling action of wind, wave and flow.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of offshore wind power generation, and particularly relates to a wind tunnel-pool combined loading distributed hybrid test method for a floating wind turbine. BACKGROUND

[0002] With the rapid development of offshore wind power and the continuous expansion of the sea scale, the resources available for development and utilization in the offshore area gradually tend to be saturated, so it is an inevitable trend for the offshore wind power industry to develop into the deep sea, and the floating wind turbine becomes a research hotspot due to its characteristics suitable for deep water areas. However, the dynamic response of the floating wind turbine under complex marine environments (wind, wave, and flow combined action) and the aerodynamic-hydrodynamic-control coupling effect are extremely challenging, and the traditional numerical simulation method is limited by theoretical assumptions and calculation accuracy, and needs to be verified through physical model tests.

[0003] At present, the test method for the floating wind turbine system is mainly a wind wave flow pool model test, which is different from the traditional marine floating structure. The huge wind wheel of the deep sea floating wind turbine bears the aerodynamic load, and the system presents complex dynamic response characteristics of aerodynamic-hydrodynamic coupling, so the scale model test needs to consider the similarity relationship of the aerodynamic load and the hydrodynamic load. For the simulation of the aerodynamic load of the wind turbine, viscous force and inertial force are dominant, and the dynamic similarity needs to follow the Reynolds number similarity criterion; and for the simulation of the hydrodynamic load of the floating platform and mooring part, gravity and inertial force are dominant, and the dynamic similarity needs to follow the Froude number similarity criterion. These two completely different similarity criteria will easily lead to the "scale conflict" phenomenon of the scale model of the offshore floating wind turbine, that is, under the same length scale ratio and the restriction of the test conditions, it is difficult to keep the Reynolds number and the Froude number similar at the same time. If the Froude number similarity is strictly used, the aerodynamic performance of the scale model will be difficult to simulate accurately, and vice versa. Moreover, with the increase of the size of the wind turbine, the difference in the scale effect will be more prominent, making it difficult to ensure the similarity of the model test, and even may cause distortion of the aerodynamic-hydrodynamic coupling characteristics. However, due to the irreconcilable contradiction between the above-mentioned Reynolds number similarity and the Froude number similarity, the pool model real-time hybrid test technology with the floating platform as the test substructure has attracted a lot of attention in recent years and has been applied initially. The basic idea is to carry out aerodynamic numerical simulation with the wind turbine as the numerical substructure, and the floating platform and mooring part are loaded in the pool as the test substructure, and the aerodynamic load obtained by numerical simulation is applied to the physical model through cables or multi-rotor actuators or fan arrays.

[0004] Chinese invention patent CN119334583A (publication number) proposes a six-degree-of-freedom aerodynamic load simulation system and control method for offshore floating wind turbine, which belongs to a real-time hybrid test system with a floating platform as a test substructure. This system does not establish a scaled model of the wind turbine blade, but simulates the six-degree-of-freedom aerodynamic load of the wind turbine through seven groups of variable-speed fan arrays. The system mainly consists of a wave pool, wave-current simulation equipment, a floating platform, a tower, a cabin, and seven groups of variable-speed fans installed on a fixed support. The fans use an inner and outer double concentric circle arrangement, and are precisely controlled by a brushless electronic speed regulator and controller. The control method uses a closed-loop PID algorithm, which collects platform motion data in real time, calculates six-degree-of-freedom load requirements, converts them into fan thrust commands, and finally generates aerodynamic loads. Although this system solves the "scale conflict" problem, the aerodynamic load comes from numerical calculation of OpenFAST software, which has many simplifications and cannot reflect the complex aerodynamic effects on the wind turbine in real wind fields.

[0005] Chinese invention patent CN117386568A (publication number) proposes a real-time hybrid model test method for offshore floating wind turbine with multiple fan drives, which also belongs to a real-time hybrid test system with a floating platform as a test substructure. This system uses a six-fan drive system as a physical execution mechanism, integrates a brushless motor and a propeller assembly through a carbon fiber cantilever, and cooperates with a load sensor to achieve precise control of thrust and torque. This method performs secondary development on OpenFAST software, modifies the ElastoDyn module to process six-degree-of-freedom motion data of the platform in real time, and generates a dynamic link library for MATLAB / Python calls. In the test, a multi-sensor system collects platform motion parameters in real time, and the host computer transmits the data to the numerical model to iteratively calculate the aerodynamic load, and then adjusts the fan speed through the PWM signal to form a closed-loop control. Still, it cannot reflect the aerodynamic load on the wind turbine in actual wind fields, and it cannot study the aerodynamic response of the wind turbine blade.

[0006] Chinese invention patent CN119878463A (publication number) proposes a floating fan physical-numerical mixed scale model test method, the core innovation of which is to solve the similarity law conflict problem in traditional test through the coordinated simulation of physical model and numerical model, which still belongs to the real-time mixed test system of the pool model of the floating platform as the test substructure. The implementation process of the method includes: 1) based on dimensional analysis, a multi-physical field coordinated scale criterion is established, and the fan structure is decomposed into a physical model and a numerical model; 2) six-rotor propellers and six-degree-of-freedom platforms are used to load the wind wheel thrust and floating body motion calculated by the numerical model, and the physical model response is monitored in real time through a three-dimensional / six-dimensional force sensor; 3) a "measurement-numerical calculation-loading" closed-loop system is constructed to realize real-time interaction above 10 Hz. However, the numerical floating body of the patent technology is based on the potential flow theory and the Morrison equation, and these simplified models may not fully capture the nonlinear effects (such as turbulence, wave breaking, etc.) in the real environment, and the mixed test relies on the accuracy of the numerical model, which may deviate from some real coupling effects.

[0007] From the current research status, the pool model real-time mixed test system with floating platform as the test substructure is the mainstream scheme, and the fan blades are used as numerical substructures to obtain aerodynamic load by numerical simulation, but the premise of carrying out real-time mixed test is that the numerical substructure model must be accurate enough, and the current aerodynamic numerical model is mainly based on the blade element momentum theory and the generalized dynamic wake theory, involving many approximate theories and empirical correction formulas, which may bring large errors to the test. Therefore, the pool model test system with hydrodynamic characteristic simulation as the core cannot meet the requirements of integrated test of floating wind turbine, and it is necessary to establish a test method that can simulate aerodynamic load and hydrodynamic load at the same time. SUMMARY

[0008] The invention is a wind tunnel-pool combined loading floating wind turbine distributed mixed test method, which uses a distributed mixed test technology of multiple test substructures, takes the wind turbine and the floating platform as two relatively independent test substructures, designs them by using different similarity criteria and geometric scale ratios, and places them in different laboratories for test loading or computer simulation, which can solve the problem of aerodynamic-hydrodynamic similarity incoordination; and the test substructures interact with each other through the network to carry out collaborative online test, so as to realize the integration and utilization of test resources in each laboratory, high-quality reproduction of aerodynamic and hydrodynamic effects; and through the aerodynamic-hydrodynamic load loading suitable for simulating the coupling effect of wind, wave and current on the floating wind turbine, the technical problems of high-precision simulation of environmental load and dynamic coupling response in scale model test are solved, and in combination with the test capabilities of the pool and the wind tunnel, high-fidelity simulation of aerodynamic load and hydrodynamic load is realized in the test system, so that the full-coupling dynamic characteristics of the floating wind turbine are completely retained.

[0009] The technical scheme adopted by the present application is as follows:

[0010] The wind tunnel-pool combined loading distributed hybrid test method of the floating wind turbine comprises the following steps:

[0011] S1, a multi-body / multi-physical field collaborative scale criterion of the floating wind turbine is established, and the overall structure of the floating wind turbine is divided into a wind turbine physical model, a floating platform physical model and a numerical model, and the wind turbine physical model is placed in a wind tunnel test environment, and the floating platform physical model is placed in a pool test environment;

[0012] S2, the wind turbine physical model, the floating platform physical model, the numerical model, the loading system and the measurement system are integrated to build a floating wind turbine physical-numerical distributed hybrid test platform;

[0013] S3, data interaction and closed-loop control of the physical-numerical hybrid test platform.

[0014] Further, in S1, the method for establishing the multi-body / multi-physical field collaborative scale criterion of the floating wind turbine is as follows:

[0015] The aerodynamic load is equivalent to the thrust of the wind wheel, and the hydrodynamic load is equivalent to the movement of the floating body. According to the dimensional analysis theory, the load-structure-response similarity law is derived to establish the multi-body / multi-physical field collaborative scale criterion of the floating wind turbine.

[0016] Further, in S1, the division method of the wind turbine physical model, the floating platform physical model and the numerical model is as follows:

[0017] According to the established scale criterion and the prototype size of the floating wind turbine, the scale ratio is determined, and the wind turbine physical model, the floating platform physical model and the numerical model are designed. The wind turbine physical model includes blades, a cabin and a tower, and is designed according to the approximate Reynolds similarity relationship and is loaded in the wind tunnel test environment. The floating platform physical model includes a floating platform, a tower and an upper truncated mooring, and is designed according to the Froude similarity relationship and is loaded in the pool test environment. The numerical model is a lower truncated mooring, and the flow field is numerically simulated and calculated in a computer system. The wind turbine physical model is set as a first physical substructure, the floating platform physical model is set as a second physical substructure, and the numerical model is set as a numerical test substructure.

[0018] Further, in S2, the method for building the floating wind turbine physical-numerical distributed hybrid test platform is as follows:

[0019] S2.1, measurement systems and loading systems are respectively arranged on the wind turbine physical model and the floating platform physical model through connecting structures;

[0020] S2.2, the data transmission channel of the test platform is established, and each data interface of the measurement system, the calculation result file of the numerical model, and the input end of the loading system are integrated into the same information storage device of the computer to establish a data closed-loop transmission channel through the computer.

[0021] Further, in S2.1, the measurement system includes a hot-wire anemometer, a first six-component force sensor, a second six-component force sensor, a third six-component force sensor, a fourth six-component force sensor, and a displacement sensor; and the loading system includes a first multi-degree-of-freedom loading table, a loading frame, a second multi-degree-of-freedom loading table, a third multi-degree-of-freedom loading table, a fourth multi-degree-of-freedom loading table, and a fifth multi-degree-of-freedom loading table.

[0022] Further, in S2.1, the measurement system and the loading system are specifically arranged as follows: the hot-wire anemometer and the first six-component force sensor are arranged at the top of the tower of the wind turbine physical model, and the first multi-degree-of-freedom loading table is arranged at the bottom of the tower of the wind turbine physical model; the second six-component force sensor and the fifth multi-degree-of-freedom loading table are arranged at the first mooring cut-off point of the floating platform physical model; the third six-component force sensor and the third multi-degree-of-freedom loading table are arranged at the second mooring cut-off point of the floating platform physical model; the fourth six-component force sensor and the fourth multi-degree-of-freedom loading table are arranged at the third mooring cut-off point of the floating platform physical model; the first mooring cut-off point is the connection between the bottom end of the mooring and the fifth multi-degree-of-freedom loading table; the second mooring cut-off point is the connection between the bottom end of the mooring and the third multi-degree-of-freedom loading table; and the third mooring cut-off point is the connection between the bottom end of the mooring and the fourth multi-degree-of-freedom loading table.

[0023] Further, in S2.2, the data closed-loop transmission channel is as follows: first physical substructure-first six-component force sensor-second physical substructure-second multi-degree-of-freedom loading table-second six-component force sensor, third six-component force sensor, and fourth six-component force sensor-numerical substructure-second physical substructure-third multi-degree-of-freedom loading table, fourth multi-degree-of-freedom loading table, and fifth multi-degree-of-freedom loading table-displacement sensor-first physical substructure-first multi-degree-of-freedom loading table-first six-component force sensor.

[0024] Further, in the S3, the data interaction and closed-loop control method is as follows: at the end of a time step after the first physical substructure test starts, the wind turbine aerodynamic load measured by the first six-component force sensor is sent to the computer as a first acquisition signal, and after deducting the influence of the gravity and inertia force of the wind turbine itself and the scale ratio conversion, a first input signal is obtained, which is then sent to the second multi-degree-of-freedom loading platform for simulation; the tension of the first mooring cut-off point measured by the second six-component force sensor, the tension of the second mooring cut-off point measured by the third six-component force sensor, and the tension of the third mooring cut-off point measured by the fourth six-component force sensor are sent to the computer as a second acquisition signal, and after the scale ratio conversion, a second input signal is obtained, which is input into the numerical model to output the additional displacement of the first mooring cut-off point, the second mooring cut-off point, and the third mooring cut-off point as a third acquisition signal, and after the scale ratio conversion, a third input signal is obtained, which is then sent to the third multi-degree-of-freedom loading platform, the fourth multi-degree-of-freedom loading platform, and the fifth multi-degree-of-freedom loading platform for simulation by the computer; the displacement of the floating platform measured by the displacement sensor is a fourth acquisition signal, and after the scale ratio conversion, a fourth input signal is obtained, which is then sent to the first multi-degree-of-freedom loading platform by the computer as an additional input for the next time step, and the process is gradually advanced in time steps until the expected number of steps or time is reached.

[0025] Compared with the prior art, the present application has the following beneficial effects:

[0026] 1、The present application combines the advantages of wind tunnel test and pool test by designing the fan part according to the approximate Reynolds number similarity, designing the floating platform physical model according to the Froude number similarity, simulating the truncated mooring by using numerical substructure, and loading the fan physical model and the floating platform physical model in the wind tunnel and the pool respectively, and coordinating the boundaries of the two through the loading system, thereby realizing high-precision synchronous simulation of aerodynamic and hydrodynamic loads, and significantly improving the reliability of the test results.

[0027] 2、The present application adopts a physical-numerical hybrid test platform, distributes each test substructure in different laboratories, realizes collaborative online testing through network data interaction, effectively avoids the limitations of single laboratory equipment capacity, and reduces the complexity of physical model manufacturing and testing by introducing numerical substructure, thereby saving raw material and process costs and improving test efficiency.

[0028] 3、The present application improves the dynamic response simulation accuracy of the floating wind turbine in complex environments through closed-loop control and dynamic load matching technology, dynamically adjusts the input signal of the loading system in real time by combining the calculation results of the numerical model with the data collected by the detection system, and ensures the synchronization and coordination of aerodynamic and hydrodynamic loads, thereby providing a high-fidelity test method for studying the aerodynamic-hydrodynamic coupling characteristics. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 It is a schematic diagram of the physical model of the wind turbine of the present application.

[0030] Figure 2 It is a schematic diagram of the physical model of the floating platform of the present application.

[0031] Figure 3 It is an enlarged view of part A of the present application.

[0032] Figure 4 It is a flow chart of the distributed hybrid test of the simultaneous loading mode of the first embodiment of the present application.

[0033] Figure 5 It is a flow chart of the distributed hybrid test of the alternate loading mode of the second embodiment of the present application.

[0034] In the figure: 1, tower drum; 2, blade; 3, first multi-degree-of-freedom loading table; 4, loading frame; 5, third multi-degree-of-freedom loading table; 6, second mooring truncation point; 7, floating platform; 8, second multi-degree-of-freedom loading table; 9, fourth multi-degree-of-freedom loading table; 10, third mooring truncation point; 11, first mooring truncation point; 12, fifth multi-degree-of-freedom loading table. DETAILED DESCRIPTION

[0035] The technical solutions of the present application will be described clearly and completely below through embodiments. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments in the present application without creative labor shall fall within the scope of protection of the present application.

[0036] Embodiment one

[0037] As shown in Figure 1 , Figure 2 , Figure 3 , Figure 4 The distributed hybrid test method of the floating wind turbine provided by the present application is provided by the present application, which comprises the following steps:

[0038] S1, establish the multi-body / multi-physical field collaborative scaling criterion of the floating wind turbine, and divide the overall structure of the floating wind turbine into a wind turbine physical model, a floating platform physical model and a numerical model, and place the wind turbine physical model in the wind tunnel test environment and the floating platform physical model in the water pool test environment;

[0039] Preferably, in the S1, the method for establishing the multi-body / multi-physical field collaborative scaling criterion of the floating wind turbine is as follows:

[0040] The aerodynamic load is equivalent to the wind wheel thrust, and the hydrodynamic load is equivalent to the floating body movement; according to the dimensional analysis theory, the load-structure-response similarity law is derived, and the multi-body / multi-physical field collaborative scale-down criterion of the floating wind turbine is established;

[0041] Preferably, in the S1, the partition methods of the wind turbine physical model, the floating platform physical model and the numerical model are as follows:

[0042] According to the established scale-down criterion and the prototype size of the floating wind turbine, the scale-down ratio is determined, and the wind turbine physical model, the floating platform physical model and the numerical model are designed; the wind turbine physical model includes the blade 2, the cabin and the tower 1, and is designed according to the approximate Reynolds similarity relationship, and is loaded in the wind tunnel experimental environment; the floating platform physical model includes the floating platform, the tower 1 and the upper truncated mooring, and is designed according to the Froude similarity relationship, and is loaded in the water pool experimental environment; the numerical model is the lower truncated mooring, and the flow field is simulated numerically, and is calculated in the computer system, wherein the wind turbine physical model is the first physical substructure; the floating platform physical model is the second physical substructure; and the numerical model is the numerical test substructure;

[0043] Since the mooring truncation point is a key node set to solve the space limitation of the water pool, the complete mooring system is truncated into two parts: the upper truncated mooring refers to the real cable part between the floating platform and the mooring truncation point in the water pool for physical modeling; the lower truncated mooring refers to the part truncated from the mooring truncation point to the seabed anchor point, which cannot be physically simulated; the mechanical effect is accurately reproduced by computer numerical simulation and combined with the equivalent force and movement applied by the multi-degree-of-freedom loading table installed at the truncation point, so as to realize the equivalent simulation of the dynamic characteristics of the full-scale mooring system;

[0044] Specifically, the wind turbine is divided into a wind turbine physical model, a floating platform physical model and a numerical model; the wind turbine physical model is the first physical substructure and is simulated in the wind tunnel; the floating platform physical model is the second physical substructure and is simulated in the water pool; the lower mooring truncated due to the limitation of the water pool depth is the numerical model and is set as the numerical substructure for calculation; since the wind turbine physical model and the floating platform physical model are two independent test models, the length scale-down ratio can be independently set;

[0045] The wind turbine physical model and the floating platform physical model both include a tower section, and the tower sections of the wind turbine physical model and the floating platform physical model only differ in scale ratio, so that the tower section data of the floating platform physical model can be loaded to the tower section of the wind turbine physical model as a command of the tower section of the wind turbine physical model for testing, and the force and motion information measured by the two physical sub-models can be restored to the prototype according to the respective similarity relationships and then converted to the other physical sub-model.

[0046] S2, integrating the wind turbine physical model, the floating platform physical model, the numerical model, the loading system and the measuring system to build a floating wind turbine physical-numerical distributed hybrid test platform;

[0047] Preferably, the method for building the floating wind turbine physical-numerical distributed hybrid test platform in S2 is as follows:

[0048] S2.1, the measuring system and the loading system are arranged on the wind turbine physical model and the floating platform physical model through the connecting structure;

[0049] Specifically, in S2.1, the measuring system includes a hot-wire anemometer, a first six-component force sensor, a second six-component force sensor, a third six-component force sensor, a fourth six-component force sensor and a displacement sensor; and the loading system includes a first multi-degree-of-freedom loading table 3, a loading frame 4, a second multi-degree-of-freedom loading table 8, a third multi-degree-of-freedom loading table 5, a fourth multi-degree-of-freedom loading table 9 and a fifth multi-degree-of-freedom loading table 12.

[0050] The specific arrangement of the measuring system and the loading system is as follows: the hot-wire anemometer and the first six-component force sensor are arranged at the top of the tower section 1 of the wind turbine physical model, and the first multi-degree-of-freedom loading table 3 is arranged at the bottom of the tower section 1 of the wind turbine physical model; the second multi-degree-of-freedom loading table 8 is arranged at the top of the tower section 1 of the floating platform physical model and connected with the loading frame 4, the displacement sensor is arranged on the floating platform of the floating platform physical model, the second six-component force sensor and the fifth multi-degree-of-freedom loading table 12 are arranged at the first mooring truncation point 11 of the floating platform physical model; the third six-component force sensor and the third multi-degree-of-freedom loading table 5 are arranged at the second mooring truncation point 6 of the floating platform physical model; the fourth six-component force sensor and the fourth multi-degree-of-freedom loading table 9 are arranged at the third mooring truncation point 10 of the floating platform physical model; the first mooring truncation point 11 is the connection between the bottom end of the mooring and the fifth multi-degree-of-freedom loading table 12; the second mooring truncation point 6 is the connection between the bottom end of the mooring and the third multi-degree-of-freedom loading table 5; and the third mooring truncation point 10 is the connection between the bottom end of the mooring and the fourth multi-degree-of-freedom loading table 9.

[0051] The hot-wire anemometer and the first six-component force sensor are arranged on the top of the tower 1 of the wind tunnel physical model, the hot-wire anemometer is used for measuring the wind speed, and the first six-component force sensor is used for measuring the top force of the tower 1 in the wind tunnel test; the first multi-degree-of-freedom loading platform 3 is arranged at the bottom of the tower 1 and is used for applying displacement to the tower 1 in the wind tunnel test; the second multi-degree-of-freedom loading platform 8 is arranged on the top of the tower 1 of the floating platform physical model and is connected to the bottom of the loading frame 4 through bolts, and is used for applying counterforce to the tower 1 of the floating platform physical model; the displacement sensor is arranged on the floating platform of the floating platform physical model and is used for measuring the displacement value of the floating platform, and the displacement value of the floating platform is loaded to the bottom of the tower 1 of the wind turbine model through data interaction as the displacement command of the tower 1 in the wind turbine physical model, that is, the displacement of the floating platform is equivalent to the displacement of the bottom of the tower 1, but the data interaction between different models still needs to be converted by the scale ratio; the second six-component force sensor, the third six-component force sensor, the fourth six-component force sensor, the third multi-degree-of-freedom loading platform 5, the fourth multi-degree-of-freedom loading platform 9 and the fifth multi-degree-of-freedom loading platform 12 are arranged on the floating platform of the floating platform physical model, the floating platform is composed of three floating platforms 7 connected with each other, the second six-component force sensor is used for measuring the tension of the first mooring cut-off point 11 in the pool test, the third six-component force sensor is used for measuring the tension of the second mooring cut-off point 6 in the pool test, and the fourth six-component force sensor is used for measuring the tension of the third mooring cut-off point 10 in the pool test; the third multi-degree-of-freedom loading platform 5 is used for applying displacement of the second mooring cut-off point 6 to the floating platform in the pool test, the fourth multi-degree-of-freedom loading platform 9 is used for applying displacement of the third mooring cut-off point 10 to the floating platform in the pool test, and the fifth multi-degree-of-freedom loading platform 12 is used for applying displacement of the first mooring cut-off point 11 to the floating platform in the pool test.

[0052] S2.2, a data transmission channel of the test platform is established, each data interface of the measurement system, the calculation result file of the numerical model and the input end of the loading system are integrated into the same information storage device of the computer, and the data closed-loop transmission channel is established through the computer;

[0053] Specifically, in the S2.2, the data closed-loop transmission channel is as follows: the first physical substructure-the first six-component force sensor-the second physical substructure-the second multi-degree-of-freedom loading platform 8-the second six-component force sensor, the third six-component force sensor and the fourth six-component force sensor-the numerical substructure-the second physical substructure-the third multi-degree-of-freedom loading platform 5, the fourth multi-degree-of-freedom loading platform 9 and the fifth multi-degree-of-freedom loading platform 12-the displacement sensor-the first physical substructure-the first multi-degree-of-freedom loading platform 3-the first six-component force sensor;

[0054] S3, data interaction and closed-loop control of the physical-numerical hybrid test platform;

[0055] Specifically, in the S3, the method of data interaction and closed-loop control is as follows: at the end of a time step after the first physical substructure test starts, the wind turbine aerodynamic load measured by the first six-component force sensor is sent to the computer as a first collection signal, and after deducting the influence of the gravity and inertial force of the wind turbine itself and the scale ratio conversion, a first input signal is obtained, which is then sent to the second multi-degree-of-freedom loading platform 8 for simulation; the tension of the first mooring cut-off point 11 measured by the second six-component force sensor, the tension of the second mooring cut-off point 6 measured by the third six-component force sensor, and the tension of the third mooring cut-off point 10 measured by the fourth six-component force sensor are sent to the computer as a second collection signal, and after the scale ratio conversion, a second input signal is obtained, which is input to the numerical model to output the additional displacement of the first mooring cut-off point 11, the second mooring cut-off point 6, and the third mooring cut-off point 10 as a third collection signal, and after the scale ratio conversion, a third input signal is obtained, which is then sent to the third multi-degree-of-freedom loading platform 5, the fourth multi-degree-of-freedom loading platform 9, and the fifth multi-degree-of-freedom loading platform 12 for simulation; the displacement of the floating platform measured by the displacement sensor is sent to the computer as a fourth collection signal, and after the scale ratio conversion, a fourth input signal is obtained, which is then sent to the first multi-degree-of-freedom loading platform 3 as an additional input for the next time step, and the process is repeated step by step until the expected number of steps or time is reached.

[0056] Embodiment Two

[0057] As shown in Figure 1 , Figure 2 , Figure 3 , Figure 5 The wind tunnel-pool combined loading distributed hybrid test method for floating wind turbines provided by the application can realize the interaction of the wind turbine and the floating body at the same time, and the test method can be used for the test of the wind turbine and the floating body with different time similarity ratios.

[0058] Step 3, first, a simplified or approximate numerical model of the overall floating wind turbine system is established, and the force time history at the top of the tower 1 and the displacement time history at the first mooring truncation point 11, the second mooring truncation point 6 and the third mooring truncation point 10 are calculated; then the above displacement and force time history are taken as the loading target to carry out the pool model test; the displacement time history of the floating platform collected by the pool test is taken as the loading target to carry out the wind tunnel model test with the first multi-degree-of-freedom loading table 3 at the bottom; at the same time, the tension time history of the first mooring truncation point 11, the second mooring truncation point 6 and the third mooring truncation point 10 collected by the pool test is sent to the numerical mooring to calculate the displacement time history of the first mooring truncation point 11, the second mooring truncation point 6 and the third mooring truncation point 10; the force time history at the top of the tower 1 measured by the wind tunnel test and the displacement time history of the first mooring truncation point 11, the second mooring truncation point 6 and the third mooring truncation point 10 obtained by numerical simulation are sent to the pool model for test loading again; so on and so forth, until the force balance and displacement coordination of the tower 1 top boundary and the first mooring truncation point 11, the second mooring truncation point 6 and the third mooring truncation point 10 boundary are realized.

[0059] For example: the force time history in the boundary condition of the top of the tower 1 and the displacement time history in the boundary condition of the first mooring truncation point 11, the second mooring truncation point 6 and the third mooring truncation point 10, both as system input and as system output, when the two time histories input in an iteration step are respectively equal to the two time histories output within the tolerance, it can be considered that the parameter converges successfully; similarly, for the process quantity, such as the displacement time history at the bottom of the tower 1, although there is an inevitable error between the command sent to the first multi-degree-of-freedom loading table 3 and the actual displacement of the first multi-degree-of-freedom loading table 3, as long as the error is within the tolerance, it is also judged to be converged, when the convergence of all substructure boundary conditions is realized, the iteration is completed, and the final structural response is obtained, and the test is completed.

[0060] The above is only a preferred example of the present application, and does not limit the present application in any form, so any modification, equivalent change and modification of the above examples according to the technical essence of the present application without departing from the technical solution content of the present application, all still belong to the scope of the technical solution of the present application.

Claims

1. A distributed hybrid test method for floating wind turbines under combined wind tunnel-water tank loading, characterized in that: Includes the following steps: S1. Establish a multi-body / multi-physics field collaborative scaling criterion for floating wind turbines. Divide the overall structure of the floating wind turbine into a wind turbine physical model, a floating platform physical model, and a numerical model. Place the wind turbine physical model in a wind tunnel experimental environment and the floating platform physical model in a water tank experimental environment. The methods for dividing the wind turbine physical model, floating platform physical model, and numerical model are as follows: The scaling ratio is determined based on the established scaling criteria and the prototype size of the floating wind turbine. A physical model of the wind turbine, a physical model of the floating platform, and a numerical model are designed. The physical model of the wind turbine includes blades (2), nacelle, and tower (1). The scaled model is designed according to the approximate Reynolds similarity relationship and is loaded in a wind tunnel experimental environment. The physical model of the floating platform includes the floating platform, tower (1), and upper truncated mooring. The scaled model is designed according to the Froude similarity relationship and is loaded in a water tank experimental environment. The numerical model is the lower truncated mooring. The flow field is numerically simulated and calculated in a computer system. The physical model of the wind turbine is set as the first physical substructure, the physical model of the floating platform is set as the second physical substructure, and the numerical model is set as the numerical test substructure. S2 integrates the physical model of the wind turbine, the physical model of the floating platform, the numerical model, the loading system and the measurement system to build a distributed hybrid physical-numerical test platform for floating wind turbines. The construction method of the floating wind turbine physical-numerical distributed hybrid test platform is as follows: S2.1, A measurement system and a loading system are respectively set on the physical model of the wind turbine and the physical model of the floating platform through the connection structure; S2.2, integrate the various data interfaces of the measurement system, the numerical model calculation result file and the input terminal of the loading system into the same information storage device of the computer, and establish a closed-loop data transmission channel through the computer; The specific setup of the measurement system and loading system is as follows: the hot wire speed meter and the first six-component force sensor are set at the top of the tower (1) of the wind turbine physical model, and the first multi-degree-of-freedom loading platform (3) is set at the bottom of the tower (1) of the wind turbine physical model; the second multi-degree-of-freedom loading platform (8) is set at the top of the tower (1) of the floating platform physical model and connected to the loading frame (4); the displacement sensor is set on the floating platform of the floating platform physical model; the second six-component force sensor and the fifth multi-degree-of-freedom loading platform (12) are both set at the first mooring cutoff point (11) of the floating platform physical model; The third six-component force sensor and the third multi-degree-of-freedom loading platform (5) are both located at the second mooring cutoff point (6) of the floating platform physical model; the fourth six-component force sensor and the fourth multi-degree-of-freedom loading platform (9) are both located at the third mooring cutoff point (10) of the floating platform physical model; the first mooring cutoff point (11) is the connection point between the bottom of the mooring and the fifth multi-degree-of-freedom loading platform (12); the second mooring cutoff point (6) is the connection point between the bottom of the mooring and the third multi-degree-of-freedom loading platform (5); the third mooring cutoff point (10) is the connection point between the bottom of the mooring and the fourth multi-degree-of-freedom loading platform (9); S3, data interaction and closed-loop control of the physical-numerical hybrid experimental platform; The data interaction and closed-loop control method is as follows: After one time step ends following the start of the first physical substructure test, the aerodynamic load of the wind turbine measured by the first six-component force sensor is sent to the computer as the first acquisition signal. After deducting the influence of the wind turbine's own gravity and inertial force and the scaling conversion, the first input signal is obtained and then sent by the computer to the second multi-degree-of-freedom loading stage (8) for simulation. The tension of the first mooring cutoff point (11) measured by the second six-component force sensor, the tension of the second mooring cutoff point (6) measured by the third six-component force sensor, and the tension of the third mooring cutoff point (10) measured by the fourth six-component force sensor are sent to the computer as the second acquisition signal. After scaling conversion, the second input signal is obtained. The number is input into the numerical model and the additional displacements of the first mooring cutoff point (11), the second mooring cutoff point (6), and the third mooring cutoff point (10) are output as the third acquisition signal. After scaling conversion, the third input signal is obtained and then sent by the computer to the third multi-degree-of-freedom loading platform (5), the fourth multi-degree-of-freedom loading platform (9), and the fifth multi-degree-of-freedom loading platform (12) respectively for simulation. The displacement of the floating platform measured by the displacement sensor is used as the fourth acquisition signal and after scaling conversion, the fourth input signal is obtained and then sent by the computer to the first multi-degree-of-freedom loading platform (3) as the additional input for the next time step. The time step is gradually advanced until the expected number of steps or time is reached.

2. The distributed hybrid test method for floating wind turbines under combined wind tunnel-water tank loading according to claim 1, characterized in that: In S1, the method for establishing the multi-body / multi-physics field collaborative scaling criterion for the floating wind turbine is as follows: By equating aerodynamic loads to wind turbine thrust and hydrodynamic loads to floating body motion, and based on dimensional analysis theory, the load-structure-response similarity law is derived, and a multi-body / multi-physics field collaborative scaling criterion for floating wind turbines is established.

3. The distributed hybrid test method for floating wind turbines under combined wind tunnel-water tank loading according to claim 1, characterized in that: In S2.1, the measurement system includes a hot-wire velocimeter, a first six-component force sensor, a second six-component force sensor, a third six-component force sensor, a fourth six-component force sensor, and a displacement sensor; the loading system includes a first multi-degree-of-freedom loading platform (3), a loading frame (4), a second multi-degree-of-freedom loading platform (8), a third multi-degree-of-freedom loading platform (5), a fourth multi-degree-of-freedom loading platform (9), and a fifth multi-degree-of-freedom loading platform (12).

4. The distributed hybrid test method for floating wind turbines under combined wind tunnel-water tank loading according to claim 3, characterized in that: In S2.2, the data closed-loop transmission channel is as follows: First physical substructure - First six-component force sensor - Second physical substructure - Second multi-degree-of-freedom loading stage (8) - Second six-component force sensor, Third six-component force sensor, Fourth six-component force sensor - Numerical substructure - Second physical substructure - Third multi-degree-of-freedom loading stage (5), Fourth multi-degree-of-freedom loading stage (9), Fifth multi-degree-of-freedom loading stage (12) - Displacement sensor - First physical substructure - First multi-degree-of-freedom loading stage (3) - First six-component force sensor.

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