Situation type triangular vortex generator and position regulation and control method

Abstract

The invention provides a displacement vortex generator and a position regulation and control method, and belongs to the field of active flow control equipment. The VG comprises a belt, a belt guide rail, a belt bearing, a sliding block, a supporting column, a triangular VG body, a guide rail supporting block, a limiting groove, a body connecting plate and a motor. The belt is arranged on the belt guide rail and is driven by the motor; the sliding block is arranged on the belt, is in an inverted concave shape and is connected with the body connecting plate through the supporting column, and the VG bodies are fixed to the two ends of the body connecting plate. The belt guide rail is arranged on the guide rail supporting block, and the sliding block can penetrate through the limiting groove. The motor is controlled to drive the belt to drive the sliding block and the VG body to move, and accurate adjustment of the position of the vortex generator body is achieved. The position of the vortex generator is automatically adjusted according to changes of the incoming flow wind speed and the attack angle, the optimal pneumatic effect is kept under different working conditions, the pneumatic performance and the power generation efficiency of the wind turbine blade are remarkably improved, and the negative influence of the front edge roughness can be effectively weakened.

Description

Technical Field

[0001] The invention belongs to the field of active flow control and equipment, and in particular relates to a position-variable triangular vortex generator and a position control method. Background Art

[0002] In the application fields of fluid dynamics such as aviation engineering and wind power generation, improving the aerodynamic performance of wings or blades has always been a hot topic and difficulty in research. The aerodynamic performance of wings or blades is directly related to the lift, drag, stability of aircraft and the efficiency of wind turbines. Especially in complex airflow environments, such as high wind speeds and large angles of attack, flow separation often occurs near the wall, which seriously reduces its aerodynamic performance and may even cause equipment failure or damage.

[0003] Flow separation refers to the phenomenon of backflow in the airfoil or blade flow, which occurs when the kinetic energy of the fluid in the boundary layer is insufficient to overcome the adverse pressure gradient due to the increase of adverse pressure gradient and the enhancement of viscous force in the boundary layer. Flow separation will not only lead to a sharp drop in the lift coefficient, but also significantly increase the drag coefficient, thus seriously affecting the operating efficiency of the blade. In order to improve the aerodynamic performance of the blade, vortex generators are usually used as flow control devices.

[0004] In the prior art, passive triangular vortex generators (VG) are generally used to improve the flow separation phenomenon on the blade surface. VG generates vortices on the blade surface to enhance the energy input of the boundary layer, thereby delaying the occurrence of flow separation. However, the passive triangular vortex generator has the following shortcomings: First, poor adaptability: the passive triangular vortex generator cannot automatically adjust its position according to the changes in the incoming wind speed and the angle of attack, so it is difficult to maintain the best aerodynamic effect under different working conditions. Especially when the angle of attack is small, the passive triangular vortex generator may not be able to fully play its role and may even produce negative effects; Second, low efficiency: while suppressing flow separation, the passive triangular vortex generator will also introduce additional resistance and energy consumption. If the position of the triangular vortex generator is unreasonable, it will not only fail to improve the lift-to-drag ratio, but may reduce the overall efficiency; Third, complex parameter design: in order to obtain good aerodynamic effects, the design of passive triangular vortex generators often needs to consider multiple parameters, such as geometric shape, installation position, angle, etc., which increases the complexity and cost of the design; Fourth, difficult maintenance: once the passive triangular vortex generator is installed, it is difficult to disassemble and replace. During long-term use, if the triangular vortex generator is damaged or fails, it will seriously affect the aerodynamic performance of the blade and the maintenance cost is high.

[0005] Based on this, researchers began to explore active triangular vortex generators and their applications. Active triangular vortex generators can adjust their positions according to changes in incoming wind speed and angle of attack, thereby maintaining the best aerodynamic effect under different working conditions. This design not only improves the adaptability and efficiency of triangular vortex generators, but also simplifies the design process and maintenance work. However, most existing active triangular vortex generators use complex mechanical structures and control systems, which result in high costs and insufficient reliability, limited flow separation effects, and other additional problems. Summary of the invention

[0006] In view of the above-mentioned defects or deficiencies in the prior art, the present invention aims to provide a position-deformable triangular vortex generator and a position control method, which automatically adjusts its position according to changes in the incoming wind speed and the angle of attack; when the angle of attack is small, the triangular vortex generator is located at the trailing edge of the suction surface slit to produce a maximum ratio of the lift coefficient to the drag coefficient; when the angle of attack is large, the triangular vortex generator is moved to the leading edge of the suction surface slit to suppress the flow separation on the suction surface under large angle of attack conditions, and can maintain the best aerodynamic effect under different working conditions. It has a simple structure, low cost and high precision, and can effectively control and optimize the position of the vortex generator, thereby improving the power generation efficiency or aerodynamic performance of the blade.

[0007] In order to achieve the above purpose, the embodiment of the present invention adopts the following technical solution:

[0008] In the first aspect, the embodiment of the present invention provides a position-deformed triangular vortex generator, including: a belt 15, a belt guide 3, a belt bearing 4, a slider 5, a support column 6, a triangular vortex generator VG body 7, a guide support block 8, a limit groove 9, a body connecting plate 11, and a motor 12; wherein,

[0009] The belt 15 is arranged on the belt guide rail 3. The belt guide rail 3 is a strip with a rectangular cross section. A motor 12 is arranged at one end and a belt bearing 4 is arranged at the other end. The motor 12 and the belt bearing 4 constitute a power device of the belt 15, driving the belt 15 to reciprocate on the belt guide rail 3; the slider 5 is arranged on the belt 15, and moves along the upper side of the belt guide rail 3 driven by the belt 15;

[0010] The slider 5 is in an inverted concave shape, with a support column 6 fixed at the middle position of the upper side, a main body connecting plate 11 fixed at the top of the support column 6, with the support column 6 as the symmetry center, triangular VG main bodies 7 are fixed at both ends of the main body connecting plate 11, and the vertical distance between the triangular VG main body 7 and the side surface of the suction surface of the current blade element is a predetermined height h; the triangular VG main body 7 is two completely identical triangular plates, namely the first main body and the second main body, which are symmetrically arranged at both ends of the main body connecting plate 11; the main body connecting plate 11 and the triangular VG main body 7 extend out of the suction surface slit 10 of the current blade element 1, and the support column 6 is parallel to the web slit, and moves along the suction surface slit 10 driven by the slider 5 and the support column 6;

[0011] A slit perpendicular to the blade element surface, penetrating the blade element 1, extending to the web 2 and connected to the limiting groove 9 is provided on the blade element 1 and the web 2 vertically fixed thereto, and having a predetermined length, a predetermined width and a predetermined depth, wherein the predetermined length and the predetermined width correspond to the blade element suction surface slit 10, and the predetermined width and the predetermined depth correspond to the web slit, wherein the width of the suction surface slit 10 is the same as the width of the web slit; at the bottom of the web slit, the slit is connected to an inverted concave limiting groove 9; the protrusion on the web in the groove is a guide rail support block 8; the upper part of the inverted concave limiting groove 9 is the same shape as the slider 5, so that the slider 5 can travel in the limiting groove 9; the belt guide rail 3 is arranged on the guide rail support blocks 8 at the bottom of at least two limiting grooves 9, and is evenly distributed between the guide rail support blocks 8, so that the belt guide rail 3 can stably support the movement of the slider 5.

[0012] As a preferred embodiment of the present invention, the slider 5 is fixed to the belt 15 by welding.

[0013] As a preferred embodiment of the present invention, the predetermined height h is 0.5% to 1.5% of the current blade chord length.

[0014] As a preferred embodiment of the present invention, the belt guide rail 3 is provided with identifiable position scales.

[0015] As a preferred embodiment of the present invention, the predetermined length of the slit is 45% to 55% of the current blade chord length, and the actual assembly range of the triangular VG body 7 is 10% to 50% of the chord position.

[0016] As a preferred embodiment of the present invention, the vortex generator further comprises: a data transmission line 13 and a control center 14;

[0017] The control center 14 is disposed on the web 2 and is connected to the motor 12 via a data transmission line 13;

[0018] The control center 14 is used to calculate the optimal VG body chordal position according to the data and control the motor 12 through the data transmission line 13.

[0019] As a preferred embodiment of the present invention, the control center 14 includes: a data acquisition module, a data processing module, an angle of attack judgment module, a model building module and a motor control module; wherein,

[0020] The data acquisition module is used to preset the angle of attack point within the blade angle of attack range, preset the VG body chord-wise position point within the VG body chord-wise position range, collect all the angle of attack points corresponding to each VG body chord-wise position point, and the corresponding lift-to-drag ratio, form an original data set, and send it to the model building module; it is also used to collect the incoming wind speed, blade speed, blade pitch angle, blade element torsion angle, and blade element radial position in the current blade environment of the triangular position variable vortex generator, and send them to the data processing module;

[0021] The data processing module is used to calculate the blade element inflow angle of attack according to the incoming wind speed, blade rotation speed, blade pitch angle, blade element twist angle, and blade element radial position, and send the current angle of attack value to the angle of attack judgment module;

[0022] The attack angle judgment module is used to judge whether the current attack angle is consistent with the attack angle at the previous moment; if they are consistent, the data acquisition module is started; if they are inconsistent, the current attack angle is sent to the model construction module;

[0023] The model building module is used to find the optimal VG body chord-wise position value at each angle of attack based on the original data set and taking the optimal lift-to-drag ratio as the objective function; to build an optimization model based on the angle of attack and the optimal VG body chord-wise position; and to input the calculated current angle of attack value into the optimization model according to the current angle of attack sent by the angle of attack judgment module, output the optimal VG body chord-wise position corresponding to the current angle of attack value, and send the optimal VG body chord-wise position to the motor control module;

[0024] The motor control module is used to control the motor using a PID algorithm according to the optimal VG body chordal position, drive the VG body to move along the belt guide rail, and move the VG body to the optimal VG body chordal position; wait until the next moment and start the data acquisition module.

[0025] In a second aspect, an embodiment of the present invention further provides a position control method of a position-deformed triangular vortex generator, which is used to control the position-deformed triangular vortex generator as described above, and the control method includes:

[0026] Step S1, preset an angle of attack point within the blade angle of attack range, preset a VG body chord-wise position point within the VG body chord-wise position range, collect all angle of attack points corresponding to each VG body chord-wise position point, and the corresponding lift-to-drag ratio to form an original data set;

[0027] Step S2, based on the original data set, taking the optimal lift-to-drag ratio as the objective function, finding the optimal VG body chord-wise position value at each angle of attack; building an optimization model based on the angle of attack and the optimal VG body chord-wise position;

[0028] Step S3, collecting the incoming wind speed, blade speed, blade pitch angle, blade element twist angle, and blade element radial position in the blade environment where the current triangular position variable vortex generator is located, and calculating the blade element inflow angle of attack;

[0029] Step S4, determining whether the current angle of attack is consistent with the angle of attack at the previous moment; if consistent, waiting until the next moment and returning to step S3; if inconsistent, proceeding to step S5;

[0030] Step S5, inputting the calculated current angle of attack value into the optimization model, and outputting the optimal VG body chord-wise position corresponding to the current angle of attack value;

[0031] Step S6, according to the optimal VG body chordal position, use PID algorithm to control the motor, drive the VG body to move along the belt guide rail, so that the VG body moves to the optimal VG body chordal position; wait until the next moment, and return to step S3.

[0032] As a preferred embodiment of the present invention, in step S2, an optimization model is constructed based on the angle of attack and the optimal VG body chord-wise position, specifically including:

[0033] Based on the angle of attack and the optimal VG body chord-wise position, an optimal position analytical table is established as an optimization model;

[0034] or,

[0035] According to the attack angle and the optimal VG body chord-wise position, function fitting is performed with the attack angle as the independent variable and the optimal VG body chord-wise position as the dependent variable, and the continuous curve function obtained after fitting is used as the optimization model.

[0036] As a preferred embodiment of the present invention, the process of calculating the blade element inflow angle of attack in step S3 is as follows:

[0037] According to formula (1), calculate the current blade inflow wind speed v r :

[0038]

[0039] In formula (1), v ∞ represents the incoming wind speed, Ω represents the blade speed, a represents the axial induction factor, a′ represents the tangential induction factor, and r represents the radial position of the blade element;

[0040] Then calculate the blade element inflow angle α according to formula (2):

[0041]

[0042] In formula (2), θ represents the sum of the blade element twist angle and the blade pitch angle.

[0043] The technical solution provided by the embodiment of the present invention has the following beneficial effects:

[0044] The position-variable triangular vortex generator and position control method provided in the embodiments of the present invention break through the technical bottleneck that the traditional passive vortex generator is fixed in position, can only increase the power generation power within a specific angle of attack, and cannot adapt to changeable wind conditions. The present invention proposes a position-variable active vortex generator device, which realizes intelligent perception of wind conditions and intelligent adjustment of the vortex generator through an active control system; based on the vortex generator control mechanism and parameter sensitivity analysis, an intelligent control strategy and optimization algorithm based on the active vortex generator are established, the incoming wind speed and blade speed are monitored by the unit sensor, the local instantaneous inflow angle of attack of the blade is calculated, the aerodynamic performance is used to optimize the best installation position, and the power-enhancing performance is evaluated; a design scheme for a position-variable active vortex generator device is proposed, with the help of servo motor control and the mechanical principle of belt drive, an actuation algorithm of the vortex generator device is established to ensure accurate real-time adjustment of the vortex generator installation position and realize dynamic control of the vortex generator for optimizing the aerodynamic performance of the blade.

[0045] Of course, it is not necessary to achieve all of the advantages described above at the same time to implement any product or method of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0047] Figure 1 3. This is a front view of the installation effect of the position-deformed triangular vortex generator according to the embodiment of the present invention;

[0048] Figure 2 This is a three-dimensional diagram of the installation effect of the position-deformed triangular vortex generator according to an embodiment of the present invention;

[0049] Figure 3 yes Figure 1 A cross-sectional view of the guide rail portion A of the modified triangular vortex generator shown;

[0050] Figure 4 yes Figure 1 A top view of the guide rail portion A of the modified triangular vortex generator shown;

[0051] Figure 5 yes Figure 2 An enlarged schematic diagram of the limiting portion B of the modified triangular vortex generator is shown;

[0052] Figure 6 is a flow chart of a method for controlling a position of a position-deformed triangular vortex generator according to an embodiment of the present invention;

[0053] Figure 7 is a blade force analysis diagram in an embodiment of the present invention;

[0054] Figure 8 The lift coefficient and drag coefficient of the triangular vortex generator of the embodiment of the present invention are compared under different attack angles for the modified triangular vortex generator, the non-triangular vortex generator and the passive triangular vortex generator when the height h is 0.8% of the local blade chord length;

[0055] Fig. 9 The lift coefficients of the triangular vortex generators described in the embodiment of the present invention are compared under different attack angles when the height h is 0.8% of the local blade chord length, the modified triangular vortex generators, the non-triangular vortex generators and the passive triangular vortex generators;

[0056] Fig.10 It is a comparison of the drag coefficients of the modified triangular vortex generator, the non-triangular vortex generator and the passive triangular vortex generator at different attack angles when the height h of the triangular vortex generator described in the embodiment of the present invention is 0.8% of the local blade chord length;

[0057] Fig.11 is the power improvement percentage of a 5MW wind turbine at different tip speed ratios when the position-deformed triangular vortex generator described in the embodiment of the present invention is neglected in terms of leading edge roughness;

[0058] Fig.12 It is the power improvement percentage of the position-deformed triangular vortex generator described in the embodiment of the present invention under different tip speed ratios of a 5MW wind turbine taking into account the leading edge roughness.

[0059] Description of reference numerals:

[0060] 1-blade element; 2-web; 3-belt guide; 4-belt bearing; 5-slider; 6-support column; 7-triangular VG body; 8-guide rail support block; 9-limiting groove; 10-suction surface slit; 11-body connecting plate; 12-motor; 13-data transmission line; 14-control center; 15-belt. DETAILED DESCRIPTION

[0061] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations. It should be noted that the embodiments of the present invention and the features in the embodiments can also be combined with each other without conflict.

[0062] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. In the description of the present invention, the terms "first", "second", "third", "fourth", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0063] In response to the problems existing in the use of triangular vortex generators, the embodiments of the present invention provide a position-deformable triangular vortex generator and a position control method, which combines the triangular vortex generator with an optimization algorithm. Starting from dynamic adaptability, intelligence and efficiency, an active triangular vortex generator is designed to avoid increased power loss at small angles of attack and improve the flow control effect of the vortex generator at large angles of attack. The vortex generator uses a sensor as a medium and a motor as a drive. It can adjust its position in real time according to the incoming flow conditions (such as angle of attack, wind speed, etc.), thereby reducing unnecessary power loss and optimizing aerodynamic performance. For example, in the field of wind power, active triangular vortex generators can further and steadily improve the power generation efficiency of wind turbines, significantly improve the efficiency of wind energy utilization, and thus produce significant economic benefits.

[0064] The position-variable triangular vortex generator and position control method described in the embodiment of the present invention can adapt to the airflow environment under different wind speeds and angles of attack by adjusting the position of the position-variable triangular vortex generator, thereby improving the aerodynamic performance of the blade. Figure 1-5 As shown, the position-deformed triangular vortex generator includes: a belt 15, a belt guide 3, a belt bearing 4, a slider 5, a support column 6, a triangular VG body 7, a guide support block 8, a limit groove 9, a body connecting plate 11, a motor 12, a data transmission line 13 and a control center 14.

[0065] The belt 15 is arranged on the belt guide rail 3, which is a strip with a rectangular cross section, with a motor 12 arranged at one end and a belt bearing 4 arranged at the other end. The motor 12 and the belt bearing 4 constitute a power device of the belt 15, driving the belt 15 to reciprocate on the belt guide rail 3. Preferably, the belt 15 is in a ring shape, including two belts, attached to the belt guide rail 3 and symmetrically distributed on both sides of the guide rail support block 8.

[0066] The slider 5 is arranged on the belt 15, and moves along the upper side of the belt guide rail 3 driven by the belt 15. The slider 5 is in an inverted concave shape, and a support column 6 is fixed at the middle position of the upper side. A body connecting plate 11 is fixed at the top of the support column 6. With the support column 6 as the symmetry center, a triangular VG body 7 is fixed at both ends of the body connecting plate 11. The vertical distance between the triangular VG body 7 and the upper side of the suction surface of the current blade element is a predetermined height h; the triangular VG body 7 is two identical triangular plates, namely the first body and the second body, which are symmetrically arranged at both ends of the body connecting plate 11. The body connecting plate 11 and the triangular VG body 7 extend out of the suction surface slit 10, and the support column 6 is parallel to the web slit. Driven by the slider 5 and the support column 6, they move along the suction surface slit 10. Preferably, the slider 5 is fixed to the belt guide rail 3 by welding. Preferably, the predetermined height h is 0.5% to 1.5% of the local blade element chord length.

[0067] On the current blade element 1 and the web 2 fixed vertically to the blade element, there is a slit perpendicular to the blade element surface, penetrating the current blade element 1 and the web 2 and connected to the limit groove 9, and having a predetermined length, predetermined width and predetermined depth. The predetermined length and predetermined width correspond to the current blade element suction surface slit 10, and the predetermined width and predetermined depth correspond to the web slit, wherein the width of the suction surface slit 10 is the same as the width of the web slit. At the bottom of the web slit, the slit is connected to an inverted concave limit groove 9; the protrusion on the web in the groove is a guide rail support block 8; the upper part of the inverted concave limit groove 9 is the same shape as the slider 5, so that the slider 5 can pass through the limit groove 9. The belt guide 3 is arranged on the guide rail support blocks 8 at the bottom of at least two limit grooves 9, and is evenly distributed between the guide rail support blocks 8, so that the belt guide 3 can stably support the movement of the slider 5. Preferably, an identifiable position scale is provided on the belt guide 3. When the slider 5 is driven by the belt to slide on the belt guide rail, the chordal position of the slider 5 is confirmed by the position scale provided on the belt guide rail 3 .

[0068] In a specific application example, the predetermined length of the slit is 45% to 55% of the current blade chord length, and the actual assembly range of the triangular VG body 7 is 10% to 50% of the chord position. That is, the opening position of the slit is between 10% and 50% of the current blade chord length, which is also the actual assembly position or activity range of the triangular VG body 7.

[0069] The control center 14 is disposed on the web 2 and connected to the motor 12 via a data transmission line 13 , and is used to calculate the optimal VG body chordwise position according to the data and control the motor 12 via the data transmission line 13 .

[0070] The control center 14 includes: a data acquisition module, a data processing module, an angle of attack judgment module, a model building module and a motor control module; wherein,

[0071] The data acquisition module is used to preset the angle of attack point within the blade angle of attack range, preset the VG body chord position point within the VG body chord position range, collect all the angle of attack points corresponding to each VG body chord position point, and the corresponding lift-to-drag ratio, form an original data set, and send it to the model building module; it is also used to collect the incoming wind speed, blade speed, blade pitch angle, blade element torsion angle, and blade element radial position in the blade environment where the current position-deformed triangular vortex generator is located, and send them to the data processing module;

[0072] The data processing module is used to calculate the blade element inflow angle of attack according to the incoming wind speed, blade rotation speed, blade pitch angle, blade element twist angle, and blade element radial position, and send the current angle of attack value to the angle of attack judgment module;

[0073] The attack angle judgment module is used to judge whether the current attack angle is consistent with the attack angle at the previous moment; if they are consistent, the data acquisition module is started; if they are inconsistent, the current attack angle is sent to the model construction module;

[0074] The model building module is used to find the optimal VG body chord-wise position value at each angle of attack based on the original data set and taking the optimal lift-to-drag ratio as the objective function; to build an optimization model based on the angle of attack and the optimal VG body chord-wise position; and to input the calculated current angle of attack value into the optimization model according to the current angle of attack sent by the angle of attack judgment module, output the optimal VG body chord-wise position corresponding to the current angle of attack value, and send the optimal VG body chord-wise position to the motor control module;

[0075] The motor control module is used to control the motor using a PID algorithm according to the optimal VG body chordal position, drive the VG body to move along the belt guide rail, and move the VG body to the optimal VG body chordal position; wait until the next moment and start the data acquisition module.

[0076] The control center controls the chord-wise position of the triangular VG body on the suction surface of the blade element, changes the airflow distribution on the suction surface of the blade element, and thus adjusts the lift coefficient and drag coefficient. Specifically, when the angle of attack is less than the preset threshold, the triangular vortex generator body is moved to the trailing edge of the suction surface slit by a motor drive. At this time, the triangular vortex generator can produce a larger ratio of lift coefficient to drag coefficient, which is beneficial to improving the aerodynamic performance of the blade or wing; when the angle of attack is greater than the preset threshold, the triangular vortex generator is moved to the leading edge of the suction surface slit by a motor drive to suppress the flow separation of the suction surface under large angle of attack conditions, and further improve the aerodynamic performance; when the wind speed and angle of attack are small, and there is no need to turn on flow control, the triangular vortex generator can be moved to the trailing edge of the blade element to avoid negative impact on aerodynamic performance, so that the triangular vortex generator can play the best effect under different working conditions.

[0077] In this embodiment, each module is implemented by a processor, and a memory is appropriately added when storage is required. Among them, the processor can be but is not limited to a microprocessor MPU, a central processing unit (CPU), a network processor (NP), a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), other programmable logic devices, discrete gates, transistor logic devices, discrete hardware components, etc. The memory can include a random access memory (RAM) and can also include a non-volatile memory (NVM), such as at least one disk storage. Optionally, the memory can also be at least one storage device located away from the aforementioned processor.

[0078] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present invention is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions can be transmitted from a website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center.

[0079] Based on the same idea, the embodiment of the present invention also provides a position control method of a position-variable triangular vortex generator, such as Figure 6 As shown, the control method comprises:

[0080] Step S1, preset an angle of attack point within the blade angle of attack range, preset a VG body chord-wise position point within the VG body chord-wise position range, collect all angle of attack points corresponding to each VG body chord-wise position point, and the corresponding lift-to-drag ratio to form an original data set.

[0081] In this step, the data is collected by requesting historical data from the blade control platform through the control center, or obtaining corresponding data through experiments based on preset angle of attack points and chord-wise position points of the VG body.

[0082] Step S2, based on the original data set, taking the optimal lift-to-drag ratio as the objective function, finding the optimal VG body chord-wise position value at each attack angle; and building an optimization model based on the attack angle and the optimal VG body chord-wise position.

[0083] In this step, the optimization model can be constructed by establishing an optimal chord-wise position analytical table as the optimization model; or, according to the angle of attack and the optimal VG body chord-wise position, the angle of attack is used as the independent variable, and the optimal VG body chord-wise position is used as the dependent variable, and function fitting is performed, and the continuous function obtained after fitting is used as the optimization model. In this case, the optimization model is a continuous curve function obtained based on the angle of attack and the optimal VG body chord-wise position.

[0084] Preferably, this step may also include: using an interpolation method to expand the basic data set to obtain a smoother and more continuous data set to improve the precision and accuracy of the optimization model. The interpolation method includes but is not limited to cubic spline interpolation.

[0085] Preferably, the lift-to-drag ratio is characterized by a ratio of a lift coefficient or a drag coefficient.

[0086] Step S3, collecting the incoming wind speed, blade speed, blade pitch angle, blade element twist angle, and blade element radial position in the blade environment where the current triangular position variable vortex generator is located, and calculating the blade element inflow angle of attack.

[0087] In this step, the incoming wind speed and blade rotation speed are generally obtained through wind speed and rotation speed sensors arranged on the suction surface.

[0088] like Figure 7 As shown, the force analysis of the blade is carried out, so the process of calculating the blade element inflow angle of attack is as follows:

[0089] According to formula (1), calculate the current blade inflow wind speed v r :

[0090]

[0091] In formula (1), v ∞ represents the incoming wind speed, Ω represents the blade speed, a represents the axial induction factor, a′ represents the tangential induction factor, and r represents the radial position of the blade element.

[0092] Then calculate the blade element inflow angle α according to formula (2):

[0093]

[0094] In formula (2), θ represents the sum of the blade element twist angle and the blade pitch angle.

[0095] Step S4, determine whether the current angle of attack is consistent with the angle of attack at the previous moment; if they are consistent, wait until the next moment and return to step S3; if they are inconsistent, enter step S5.

[0096] In this step, the judgment logic of whether the angle of attack is consistent is as follows: if the difference between the current angle of attack and the angle of attack at the previous moment and the ratio of the angle of attack at the previous moment are greater than a preset threshold, it is judged as inconsistent, otherwise it is judged as consistent. The preset threshold is set according to the actual situation, for example, 2%.

[0097] Preferably, the current moment and the previous moment are set according to the actual operation situation of the blade, and can be set as data collection points at equal time intervals, or can be set according to the corresponding time calculated based on the blade rotation angles at the same intervals.

[0098] Step S5, input the calculated current angle of attack value into the optimization model, and output the optimal VG body chord-wise position corresponding to the current angle of attack value.

[0099] Step S6, according to the optimal VG body chordal position, use PID algorithm to control the motor, drive the VG body to move along the belt guide rail, so that the VG body moves to the optimal VG body chordal position; wait until the next moment, and return to step S3.

[0100] As described above, the position-deformed triangular vortex generator described in the embodiment of the present invention can be applied to a variety of different scenarios. Taking the blades of a wind turbine as an example, when the vortex generator described in the embodiment of the present invention is used, the chordal position of the vortex generator can be adjusted differently at different blade attack angles, thereby improving the power generation efficiency and output power of the entire wind turbine.

[0101] The performance of the blades equipped with the position-deformed triangular vortex generators according to the embodiments of the present invention is evaluated, and the evaluation process is as follows:

[0102] Using the data shown in Table 1:

[0103] Table 1

[0104]

[0105] When the height of the triangular vortex generator is fixed, the lift coefficient and drag coefficient of the triangular vortex generator at the optimal chordwise position and without the triangular vortex generator are compared at different attack angles. Figure 8It can be seen that when a certain incoming wind speed is determined and the angle of attack is less than 13°, the lift coefficient and drag coefficient of the triangular vortex generator without the triangular vortex generator are larger than those when the triangular vortex generator is installed. It can be seen that at this time, the triangular vortex generator has a negative effect on the power generation of the wind turbine blades; when a certain incoming wind speed is determined and the angle of attack is greater than 13°, the lift coefficient and drag coefficient of the position-deformed triangular vortex generator are larger than those when there is no triangular vortex generator. At this time, the position-deformed triangular vortex generator has a positive effect on the power generation of the blades.

[0106] The power generation efficiency of the wind turbine is analyzed based on the working principle of the vortex generator.

[0107] A certain type of wind turbine is selected, the rotor radius R is known, and according to the linear interpolation performed in the data optimization, the sum of the blade element twist angle and the blade pitch angle θ and the chord length c at different blade element radial positions r are obtained.

[0108] Dynamic pressure q under radial velocity ∞ (density is the density under standard atmospheric pressure) can be obtained from the following formula (3):

[0109]

[0110] In formula (3), ρ represents the air density.

[0111] According to the following formulas (4) and (5):

[0112] L = q ∞ ·C l ·c (4)

[0113] D=q ∞ ·C d ·c (5)

[0114] In formulas (4)-(5), L represents lift, D represents drag, and C l is the lift coefficient, C d represents the drag coefficient and c represents the chord length.

[0115] The lift L and drag D can be obtained.

[0116] The moment calculation formulas (6), (7), and (8) under unit chord length are as follows:

[0117] T=L sin(θ+α)-D cos(θ+α) (6)

[0118] N=L cosα+D cosα (7)

[0119] T q =N sinθ+T cosθ (8)

[0120] In equations (6)-(8), T represents the tangential force component of the blade element, N represents the normal force component of the blade element, and T q Represents the internal force component of a single blade along the rotor plane.

[0121] Through T q The torque M can be obtained by integrating the radius of r, as shown in formula (9):

[0122]

[0123] In formula (9), R represents the radius of the wind wheel.

[0124] Finally, according to formula (10):

[0125] P=M·Ω (10)

[0126] Get the power P.

[0127] The tip speed ratio λ is a key parameter in wind turbine design and performance analysis. It is equal to the ratio of the linear velocity of the wind turbine blade tip to the wind speed. From the definition, it can be seen that the wind speed is inversely proportional to the tip speed ratio. Since the wind speed is positively correlated with the angle of attack, it means that the smaller the angle of attack, the greater the tip speed ratio.

[0128] Tip speed ratio:

[0129] Tip speed: v tip =Ω·R

[0130] Considering the actual situation, the leading edge roughness and tip speed ratio, which have a greater impact on the aerodynamic performance of wind turbines, are comprehensively considered. The two cases of leading edge roughness under roughness and smoothness, as well as the power enhancement performance under different tip speed ratios are compared. Finally, it is concluded that the position-deformed vortex generator has a great influence on efficiency improvement. For NREL 5MW, without considering the leading edge roughness, compared with the passive vortex generator, Fig.11 As shown in the figure, when λ=7, the power increase percentage of the position-variable vortex generator (5.67%) is 1.24% higher than that of the passive vortex generator (4.43%); when λ=8, the power increase percentage of the position-variable vortex generator (3.24%) is 1.39% higher than that of the passive vortex generator (1.85%), which significantly improves the power generation efficiency of the wind turbine. At the same time, when λ=9, the power increase percentage of the position-variable vortex generator is 1.40%, and the power increase percentage of the passive vortex generator is -0.11%; when λ=10, the power increase percentage of the position-variable vortex generator is 0.13%, and the power increase percentage of the passive vortex generator is -1.44%, which makes up for the power loss caused by the passive type and improves the power generation efficiency of the wind turbine.

[0131] More importantly, when the leading edge roughness is taken into account, the position-deformed vortex generator weakens the negative impact of the leading edge roughness and reduces the sensitivity of the airfoil aerodynamic characteristics to the roughness. Fig.12 As shown in the figure, when λ=7, the power loss is 22.29% when there is no vortex generator, and the power loss is 10.31% when equipped with a passive vortex generator, but the power loss is only 7.78% when equipped with a position-variable vortex generator, which greatly reduces the negative impact of the leading edge roughness. Moreover, when λ=12, the power loss of the passive vortex generator is even higher than that of the one without vortex generator, while the position-variable vortex generator reduces the power loss from 17.09% of the passive vortex generator to 13.63%, which is much lower than the power loss of the one without vortex generator (16.05%) and the passive vortex generator (17.09%), which alleviates the negative impact of the leading edge roughness.

[0132] In summary, the position-variable triangular vortex generator and position control method provided in the embodiments of the present invention break through the technical bottleneck that the traditional passive vortex generator is fixed in position, can only increase the power generation power within a specific angle of attack, and cannot adapt to changeable wind conditions. The present invention proposes a position-variable active vortex generator device, which realizes intelligent perception of wind conditions and intelligent adjustment of the vortex generator through an active control system; based on the vortex generator control mechanism and parameter sensitivity analysis, an intelligent control strategy and optimization algorithm based on the active vortex generator are established, the incoming wind speed and blade speed are monitored by the unit sensor, the local instantaneous inflow angle of attack of the blade is calculated, the aerodynamic performance is used to optimize the best installation position, and the power-enhancing performance is evaluated; a design scheme for a position-variable active vortex generator device is proposed, with the help of servo motor control and the mechanical principle of belt drive, an actuation algorithm of the vortex generator device is established to ensure accurate real-time adjustment of the vortex generator installation position and realize dynamic control of the vortex generator for optimizing the aerodynamic performance of the blade.

[0133] The above description is only a preferred embodiment of the present invention and an explanation of the technical principles used. It is not intended to limit the scope of the invention claimed for protection, but only represents the preferred embodiment of the present invention. Those skilled in the art should understand that the scope of the invention involved in the present invention is not limited to the technical solution formed by a specific combination of the above-mentioned technical features, but should also cover other technical solutions formed by any combination of the above-mentioned technical features or their equivalent features without departing from the inventive concept. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present invention.

Claims

1. A position-deformed triangular vortex generator, characterized in that: include: A belt (15), a belt guide rail (3), a belt bearing (4), a slider (5), a support column (6), a triangular vortex generator VG body (7), a guide rail support block (8), a limit groove (9), a body connecting plate (11), and a motor (12); wherein: The belt (15) is arranged on the belt guide rail (3). The belt guide rail (3) is a strip with a rectangular cross section. A motor (12) is arranged at one end and a belt bearing (4) is arranged at the other end. The motor (12) and the belt bearing (4) constitute a power device of the belt (15) to drive the belt (15) to reciprocate on the belt guide rail (3). The slider (5) is arranged on the belt (15) and moves along the upper side of the belt guide rail (3) driven by the belt (15). The slider (5) is in an inverted concave shape, with a support column (6) fixed at the middle position of the upper side, a main body connecting plate (11) fixed at the top of the support column (6), with the support column (6) as the symmetry center, triangular VG main bodies (7) fixed at both ends of the main body connecting plate (11), and the vertical distance between the triangular VG main body (7) and the side surface of the suction surface of the current blade element is a predetermined height h; the triangular VG main body (7) is two completely identical triangular plates, namely a first main body and a second main body, which are symmetrically arranged at both ends of the main body connecting plate (11); the main body connecting plate (11) and the triangular VG main body (7) extend out of the suction surface slit (10) of the current blade element (1), the support column (6) is parallel to the web slit, and moves along the suction surface slit (10) driven by the slider (5) and the support column (6); A slit having a predetermined length, a predetermined width and a predetermined depth is provided on the current blade element (1) and the web (2) vertically fixed to the blade element, the slit passes through the current blade element (1), extends to the web (2) and communicates with the limit groove (9), wherein the predetermined length and the predetermined width correspond to the current blade element suction surface slit (10), and the predetermined width and the predetermined depth correspond to the web slit, wherein the width of the suction surface slit (10) is the same as the width of the web slit; at the bottom of the web slit, The slit is connected to an inverted concave limiting groove (9); the protrusion on the web in the groove is a guide rail support block (8); the upper portion of the inverted concave limiting groove (9) is the same shape as the slider (5), so that the slider (5) can pass through the limiting groove (9); the belt guide rail (3) is arranged on the guide rail support blocks (8) at the bottom of at least two limiting grooves (9) and is evenly distributed between the guide rail support blocks (8), so that the belt guide rail (3) can stably support the movement of the slider (5).

2. The position-deformed triangular vortex generator according to claim 1, characterized in that: The slider (5) is fixed on the belt (15) by welding.

3. The position-deformed triangular vortex generator according to claim 1, characterized in that: The predetermined height h is 0.5% to 1.5% of the current blade chord length.

4. The position-deformed triangular vortex generator according to claim 1, characterized in that: The belt guide rail (3) is provided with identifiable position scales.

5. The position-deformed triangular vortex generator according to claim 1, characterized in that: The predetermined length of the slit is 45% to 55% of the current blade chord length, and the actual assembly range of the triangular VG body (7) is 10% to 50% of the chord position.

6. The position-deformed triangular vortex generator according to any one of claims 1 to 5, characterized in that: The vortex generator further comprises: a data transmission line (13) and a control center (14); The control center (14) is arranged on the web (2) and is connected to the motor (12) via a data transmission line (13); The control center (14) is used to calculate the optimal VG body chordal position based on the data and control the motor (12) through the data transmission line (13).

7. The position-deformed triangular vortex generator according to claim 6, characterized in that: The control center (14) comprises: a data acquisition module, a data processing module, an angle of attack judgment module, a model building module and a motor control module; wherein: The data acquisition module is used to preset the angle of attack point within the blade angle of attack range, preset the VG body chord-wise position point within the VG body chord-wise position range, collect all the angle of attack points corresponding to each VG body chord-wise position point, and the corresponding lift-to-drag ratio, form an original data set, and send it to the model building module; it is also used to collect the incoming wind speed, blade speed, blade pitch angle, blade element torsion angle, and blade element radial position in the current blade environment of the triangular position variable vortex generator, and send them to the data processing module; The data processing module is used to calculate the blade element inflow angle of attack according to the incoming wind speed, blade rotation speed, blade pitch angle, blade element twist angle, and blade element radial position, and send the current angle of attack value to the angle of attack judgment module; The attack angle judgment module is used to judge whether the current attack angle is consistent with the attack angle at the previous moment; if they are consistent, the data acquisition module is started; if they are inconsistent, the current attack angle is sent to the model construction module; The model building module is used to find the optimal VG body chord-wise position value at each angle of attack based on the original data set and taking the optimal lift-to-drag ratio as the objective function; to build an optimization model based on the angle of attack and the optimal VG body chord-wise position; and to input the calculated current angle of attack value into the optimization model according to the current angle of attack sent by the angle of attack judgment module, output the optimal VG body chord-wise position corresponding to the current angle of attack value, and send the optimal VG body chord-wise position to the motor control module; The motor control module is used to control the motor using a PID algorithm according to the optimal VG body chordal position, drive the VG body to move along the belt guide rail, and move the VG body to the optimal VG body chordal position; wait until the next moment and start the data acquisition module.

8. A method for controlling the position of a position-deformable triangular vortex generator, characterized in that: Used to control the position-deformed triangular vortex generator according to any one of claims 1 to 7, the control method comprising: Step S1, preset an angle of attack point within the blade angle of attack range, preset a VG body chord-wise position point within the VG body chord-wise position range, collect all angle of attack points corresponding to each VG body chord-wise position point, and the corresponding lift-to-drag ratio to form an original data set; Step S2, based on the original data set, taking the optimal lift-to-drag ratio as the objective function, finding the optimal VG body chord-wise position value at each angle of attack; building an optimization model based on the angle of attack and the optimal VG body chord-wise position; Step S3, collecting the incoming wind speed, blade speed, blade pitch angle, blade element twist angle, and blade element radial position in the blade environment where the current triangular position variable vortex generator is located, and calculating the blade element inflow angle of attack; Step S4, determining whether the current angle of attack is consistent with the angle of attack at the previous moment; if consistent, waiting until the next moment and returning to step S3; if inconsistent, proceeding to step S5; Step S5, inputting the calculated current angle of attack value into the optimization model, and outputting the optimal VG body chord-wise position corresponding to the current angle of attack value; Step S6, according to the optimal VG body chordal position, use PID algorithm to control the motor, drive the VG body to move along the belt guide rail, so that the VG body moves to the optimal VG body chordal position; wait until the next moment, and return to step S3.

9. The position control method according to claim 8, characterized in that: In step S2, an optimization model is constructed based on the angle of attack and the optimal VG body chord-wise position, which specifically includes: Based on the angle of attack and the optimal VG body chord-wise position, an optimal position analytical table is established as an optimization model; or, According to the attack angle and the optimal VG body chord-wise position, function fitting is performed with the attack angle as the independent variable and the optimal VG body chord-wise position as the dependent variable, and the continuous curve function obtained after fitting is used as the optimization model.

10. The position control method according to claim 8, characterized in that: The process of calculating the blade element inflow angle of attack in step S3 is as follows: According to formula (1), calculate the current blade inflow wind speed v r : In formula (1), v ∞ represents the incoming wind speed, Ω represents the blade speed, a represents the axial induction factor, a′ represents the tangential induction factor, and r represents the radial position of the blade element; Then calculate the blade element inflow angle α according to formula (2): In formula (2), θ represents the sum of the blade element twist angle and the blade pitch angle.

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