Design method of self-adaptive telescopic lift-drag composite vertical axis wind turbine

Abstract

The invention discloses a method for designing a self-adaptive telescopic lift-drag composite vertical axis wind turbine, which comprises the following steps of: determining design parameters, and optimizing a plurality of parameters according to a height-diameter ratio H / D; determining a plurality of optimization parameters; constructing a geometric model of the vertical axis wind wheel and the energy gathering plate through parameter combination, and performing automatic grid division; adjusting a parameter range according to a range analysis result, repeating the steps S2-S3 until all parameters reach extreme values, and outputting an optimal parameter combination; the expansion and contraction proportion and dynamic response characteristics of the resistance type blade are controlled through the self-adaptive expansion and contraction mechanism, and the aerodynamic performance of the resistance type blade in different expansion and contraction states is verified through numerical simulation; optimizing the matching relation between the blade expansion ratio and the tip speed ratio lambda; and S5, if the design parameters are not met, repeating the steps S1 to S5 until a final design scheme is output. According to the method, accurate matching of geometric parameters of the wind wheel and the energy gathering plate is achieved, and efficient energy capture of the wind turbine under different wind speed conditions is achieved.

Description

Technical Field

[0001] This invention relates to the technical field of wind turbines, and in particular to a design method for an adaptive telescopic lift-drag composite vertical axis wind turbine. Background Technology

[0002] While traditional lift-drag hybrid vertical axis wind turbines (SD-VAWTs) combine the advantages of lift and drag blades, they still suffer from significant drawbacks in practical applications. Their efficiency is low in low wind speed environments, primarily due to severe airflow separation, insufficient effective frontal area, and inadequate acceleration of local wind speeds. In existing technologies, the design of the energy-concentrating plate (guide vane) relies heavily on empirical parameters, lacking systematic optimization methods, resulting in wind energy utilization efficiency (Cp) generally below 0.4. Furthermore, the shape design of the drag blades does not fully utilize mathematical tools such as Bézier curves, limiting performance improvements in lift-drag hybrid turbines. Additionally, there is a contradiction between the structure and aerodynamic performance of traditional lift-drag hybrid blades, leading to an efficiency drop of over 20% at rated wind speeds. These problems severely restrict the application effectiveness and economic benefits of lift-drag hybrid vertical axis wind turbines in complex wind farm environments. Therefore, a lift-drag hybrid design method and an adaptive telescopic mechanism control strategy are urgently needed to improve the dynamic adaptability and energy capture efficiency of vertical axis wind turbines. Summary of the Invention

[0003] To address the shortcomings of existing technologies, the present invention aims to provide a design method for an adaptive telescopic lift-drag composite vertical axis wind turbine, solving the problems of low efficiency and poor start-up performance of traditional lift-type vertical axis wind turbines under low wind speed conditions, and effectively improving wind energy utilization. To achieve the above-mentioned objectives and other advantages of the present invention, a design method for an adaptive telescopic lift-drag composite vertical axis wind turbine is provided, comprising:

[0004] S1. Determine the design parameters and optimize multiple parameters based on the height-to-diameter ratio H / D;

[0005] S2. Determine multiple optimization parameters;

[0006] S3. Generate multiple sets of parameter combinations based on the orthogonal test table, construct the geometric model of the vertical axis wind turbine and the energy-concentrating plate according to the parameter combinations, and perform automated mesh generation;

[0007] S4. Adjust the parameter range based on the range analysis results, repeat steps S2-S3 until all parameters reach their extreme values, and output the optimal parameter combination.

[0008] S5. By using an adaptive telescoping mechanism, control the telescoping ratio and dynamic response characteristics of the drag-type blades, and verify the aerodynamic performance of the drag-type blades under different telescoping states through numerical simulation; optimize the matching relationship between the blade telescoping ratio and the tip speed ratio λ.

[0009] S6. Based on the numerical simulation results, adjust the blade geometry parameters and the control strategy of the telescopic mechanism until the design parameters are met. If they are not met, repeat steps S1-S5 until the final design scheme is output.

[0010] Preferably, the design parameters in step S1 include wind speed U, design power P, and wind energy utilization rate Cp, and the basic geometric parameters of the wind turbine blades are determined by wind speed U, design power P, and wind energy utilization rate Cp.

[0011] Preferably, the optimization of multiple parameters based on the height-to-diameter ratio H / D in step S1 specifically involves optimizing multiple parameters, including the outer diameter D of the lifting rotor, the lifting airfoil, the number of lifting blades Z, and the drag-type outer diameter d, based on the height-to-diameter ratio H / D of the lifting rotor.

[0012] The optimized range of the aspect ratio H / D is 1.5-3.0; the lifting airfoil is a NACA symmetrical airfoil; the number of blades Z is 2-4; and the drag type outer diameter d ranges from 0.1D to 0.3D.

[0013] Preferably, in step S2, the airfoil chord length coefficient C, the gap coefficient between the wind turbine and the concentrator plate δ, the concentrator plate inlet angle β1, the concentrator plate outlet angle β2, the number of concentrator plate blades Z1, the y-coordinates B1y of drag-type Bezier control point 1, B2y of drag-type Bezier control point 2, B3x of drag-type Bezier control point 3, and B3y of drag-type Bezier control point 3 are selected as orthogonal optimization parameters, and their optimization range is set.

[0014] Compared with existing technologies, the beneficial effects of this invention are as follows: By combining a concentrating plate structure with an adaptive telescopic lift-drag composite rotor mechanism, efficient energy capture of the wind turbine under different wind speed conditions is achieved. Through orthogonal experiments and numerical simulations, with the goal of maximizing wind energy utilization rate (Cp), precise matching of the geometric parameters of the wind turbine and the concentrating plate is achieved. By optimizing the matching relationship between the blade geometric parameters and the adaptive telescopic mechanism, and verifying aerodynamic performance through numerical simulations, the invention addresses the problems of low parameter optimization efficiency and poor global convergence in existing technologies through a combination of orthogonal experiments and range analysis. The core principle lies in dynamically adjusting the geometric parameters of the wind turbine and the concentrating plate with wind energy utilization rate (Cp) as the optimization objective, achieving optimal matching between the lift-drag composite effect and the energy-concentrating flow. This method significantly improves wind energy utilization rate while enhancing adaptability. Attached Figure Description

[0015] Figure 1 A flowchart illustrating the design method of the adaptive telescopic lift-drag composite vertical axis wind turbine according to the present invention;

[0016] Figure 2A schematic diagram of a wind turbine structure according to the adaptive telescopic lift-drag composite vertical axis wind turbine design method of the present invention;

[0017] Figure 3 A schematic diagram of blade motion for the adaptive telescopic lift-drag composite vertical axis wind turbine design method according to the present invention;

[0018] Figure 4 Optimization parameters for the energy-concentrating plate and wind turbine blades according to the adaptive telescopic lift-drag composite vertical axis wind turbine design method of the present invention;

[0019] Figure 5 A comparison diagram of the wind turbine and energy-concentrating plate before and after optimization of the adaptive telescopic lift-drag composite vertical axis wind turbine design method according to the present invention;

[0020] Figure 6 This is a comparison chart of the start-up performance and wind energy utilization rate Cp of the lift-drag composite wind turbine based on the adaptive telescopic lift-drag composite vertical axis wind turbine design method of the present invention and the traditional lift-drag composite wind turbine. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] Reference Figure 1 A design method for an adaptive telescopic lift-drag composite vertical axis wind turbine includes the following steps:

[0023] S1. Determine the design parameters and optimize multiple parameters based on the height-to-diameter ratio H / D. The design parameters include wind speed U (range: 2-25 m / s), design power P, and wind energy utilization rate Cp (initially set at 0.35-0.45). The height-to-diameter ratio of the wind turbine is determined based on these design parameters. Using the height-to-diameter ratio H / D, parameters including the outer diameter D of the lifting rotor, the lifting airfoil, the number of lifting blades Z, and the outer diameter d of the drag rotor are optimized. The calculation formulas are shown below:

[0024]

[0025] The parameters of the lift-drag composite vertical axis wind turbine were determined. The lift airfoil, the number of blades Z (lift profile), and the drag profile outer diameter d were set and optimized within their respective ranges. The height-to-diameter ratio H / D was optimized within the range of 1.5-3.0. The lift airfoil was a NACA symmetrical airfoil, specifically NACA0012, NACA0016, NACA0018, NACA0021, or NACA0025. The number of blades Z ranged from 2 to 4. The drag profile outer diameter d ranged from 0.1D to 0.3D. The calculation formulas are shown below:

[0026]

[0027] C p =λC m (5)

[0028] σ=ZC / D (6)

[0029] S2. Determine multiple optimization parameters; select nine parameters as orthogonal optimization parameters, including airfoil chord length C, concentrating plate inlet angle β1, concentrating plate outlet angle β2, concentrating plate-rotor clearance δ, y-coordinate B1y of drag-type Bezier control point 1, y-coordinate B2y of drag-type Bezier control point 2, x-coordinate B3x of drag-type Bezier control point 3, and y-coordinate B3y of drag-type Bezier control point 4. The value range of the orthogonal optimization parameters is shown in Table 1.

[0030] Table 1. Range of Orthogonal Optimization Parameters

[0031]

[0032] S3. Based on the orthogonal experimental table, multiple parameter combinations are generated. A geometric model of the vertical axis wind turbine and energy-concentrating plate is constructed according to these parameter combinations, and automated mesh generation is performed. The parameter combinations are assigned using an L27 (9 factors, 3 levels) orthogonal table. The mesh generation and solution process are automated through script code. Through numerical simulation and aerodynamic performance verification, the turbulence model of the CFD method is: SST k-ω; boundary conditions: inlet wind speed is the design wind speed U, outlet static pressure is atmospheric pressure; an unstructured mesh is used, and the near-wall boundary layer mesh is refined to Y. + =1; Analyze the torque coefficient C m Wind energy utilization rate C p Key parameters such as wind energy utilization rate (C) are used to evaluate aerodynamic efficiency. p To optimize the objective, the optimal parameter combination is selected through range analysis.

[0033] S4. Adjust the parameter range based on the range analysis results, repeat steps S2-S3 until all parameters reach their extreme values, and output the optimal parameter combination.

[0034] S5. The extension / retraction ratio and dynamic response characteristics of the drag-type blade are controlled through an adaptive telescoping mechanism. The aerodynamic performance of the drag-type blade under different extension / retraction states is verified through numerical simulation. The extension / retraction ratio range of the adaptive telescoping mechanism is 10%-90%. The aerodynamic performance of the drag-type blade under different extension / retraction states is verified through numerical simulation, and the matching relationship between the blade extension / retraction ratio and the tip speed ratio λ is optimized. The wind energy utilization rate C is analyzed. p Torque coefficient C m The optimal matching relationship between the tip velocity ratio and the expansion ratio is determined based on the flow separation characteristics.

[0035] S6. Based on the numerical simulation results, adjust the blade geometry parameters and the control strategy of the telescopic mechanism until the design parameters are met. If not, repeat steps S1-S5 until the final design scheme is output. The final scheme output includes: the geometric parameter combination of the lift-drag composite rotor and the energy-concentrating plate structure; and the specific drive logic and control strategy of the adaptive telescopic mechanism. Verify the feasibility and performance improvement effect of the design scheme through prototype testing.

[0036] In summary, by combining a concentrating plate structure with an adaptive telescopic lift-drag composite rotor mechanism, efficient energy capture of wind turbines under different wind speed conditions is achieved. The method includes: determining blade geometric parameters and their optimization range; using an adaptive telescopic drag rotor based on wind field characteristics; and achieving precise matching of the rotor and concentrating plate geometric parameters through orthogonal experiments and numerical simulations, with the goal of maximizing wind energy utilization rate (Cp). The method further includes: defining the optimization range of geometric parameters for vertical axis wind turbine blades and concentrating plates, generating orthogonal experimental combinations; constructing a three-dimensional model based on the parameters and automatically meshing it; calculating Cp for each group through CFD simulation, combining range analysis to screen primary and secondary influencing factors, dynamically iteratively adjusting the parameter range until convergence to the global optimum; optimizing the matching of blade telescopic ratio and tip speed ratio λ; and finally outputting a wind turbine design scheme that meets the dynamic wind field requirements. This invention solves the problems of low efficiency and poor start-up performance of traditional lift-type vertical axis wind turbines under low wind speed conditions, effectively improving wind energy utilization.

[0037] The number of devices and processing scale described herein are for simplification of the invention. Applications, modifications, and variations of this invention will be readily apparent to those skilled in the art. Although embodiments of the invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. It can be applied to various fields suitable for this invention, and further modifications can be readily implemented by those skilled in the art. Therefore, without departing from the general concept defined by the claims and their equivalents, this invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A design method for an adaptive telescopic lift-drag composite vertical axis wind turbine, characterized in that, Includes the following steps: S1. Determine the design parameters and optimize multiple parameters based on the height-to-diameter ratio H / D; S2. Determine multiple optimization parameters; S3. Generate multiple sets of parameter combinations based on the orthogonal test table, construct the geometric model of the vertical axis wind turbine and the energy-concentrating plate according to the parameter combinations, and perform automated mesh generation; S4. Adjust the parameter range based on the range analysis results, repeat steps S2-S3 until all parameters reach their extreme values, and output the optimal parameter combination. S5. By using an adaptive telescoping mechanism, control the telescoping ratio and dynamic response characteristics of the drag-type blades, and verify the aerodynamic performance of the drag-type blades under different telescoping states through numerical simulation; optimize the matching relationship between the blade telescoping ratio and the tip speed ratio λ. S6. Based on the numerical simulation results, adjust the blade geometry parameters and the control strategy of the telescopic mechanism until the design parameters are met. If they are not met, repeat steps S1-S5 until the final design scheme is output.

2. The design method for an adaptive telescopic lift-drag composite vertical axis wind turbine as described in claim 1, characterized in that, The design parameters mentioned in step S1 include wind speed U, design power P, and wind energy utilization rate Cp, and the basic geometric parameters of the wind turbine blades are determined by wind speed U, design power P, and wind energy utilization rate Cp.

3. The design method for an adaptive telescopic lift-drag composite vertical axis wind turbine as described in claim 1, characterized in that, In step S1, the optimization of multiple parameters based on the height-to-diameter ratio H / D is specifically carried out as follows: based on the height-to-diameter ratio H / D of the lifting rotor, the optimization of multiple parameters including the outer diameter D of the lifting rotor, the lifting airfoil, the number of lifting blades Z, and the drag outer diameter d is carried out. The optimized range of the aspect ratio H / D is 1.5-3.0; the lifting airfoil is a NACA symmetrical airfoil; the number of blades Z is 2-4; and the drag type outer diameter d ranges from 0.1D to 0.3D.

4. The design method of an adaptive telescopic lift-drag composite vertical axis wind turbine as described in claim 1, characterized in that, In step S2, the airfoil chord length coefficient C, the gap coefficient between the wind turbine and the concentrator plate δ, the inlet angle β1 of the concentrator plate, the outlet angle β2 of the concentrator plate, the number of blades of the concentrator plate Z1, the y-coordinates B1y of drag-type Bezier control point 1, B2y of drag-type Bezier control point 2, B3x of drag-type Bezier control point 3, and B3y of drag-type Bezier control point 3 are selected as orthogonal optimization parameters, and their optimization range is set.

5. The design method of an adaptive telescopic lift-drag composite vertical axis wind turbine as described in claim 4, characterized in that, The energy-concentrating plate is a tapered flow guide structure, symmetrically distributed on both sides of the vertical axis impeller, forming an aerodynamic layout of energy-concentrating, speed-increasing, and drag-increasing composite structure with the lift-drag composite rotor.

6. The design method of an adaptive telescopic lift-drag composite vertical axis wind turbine as described in claim 1, characterized in that, The adaptive telescopic mechanism described in step S5 is hydraulically driven, and the telescopic ratio of the drag-type blades ranges from 10% to 90% of the outer diameter D of the lift-type rotor. The optimal matching relationship between the tip speed ratio and the telescopic ratio is determined by analyzing the wind energy utilization rate Cp, the torque coefficient Cm, and the flow separation characteristics.

7. The design method for an adaptive telescopic lift-drag composite vertical axis wind turbine as described in claim 4, characterized in that, The optimization range of the orthogonal optimized airfoil chord length C is 0.05D-0.15D; the optimization range of the inlet angle β1 and outlet angle β2 is 15°~35°; the optimization range of the energy-concentrating plate and wind turbine gap δ is 0.035D-0.075D; the y-coordinate B1y of drag-type Bezier control point 1 is 0-0.2; the y-coordinate B2y of drag-type Bezier control point 2 is 0.176-0.276; the x-coordinate B3x of drag-type Bezier control point 3 is 0.676-0.876; and the y-coordinate B3y of drag-type Bezier control point 3 is 0.224-0.424.

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