Turbulent boundary layer drag reduction experiment device based on micro vortex generator array

Abstract

The invention belongs to the technical field of resistance reduction, and discloses a turbulent boundary layer resistance reduction experiment device based on a micro vortex generator array, which comprises a friction force capture module, a single-degree-of-freedom air floating platform and a four-degree-of-freedom coarse adjustment base which are sequentially mounted from top to bottom, the friction force capturing module comprises a friction force sensing flat plate and a micro vortex generator array mounted above the friction force sensing flat plate, the micro vortex generator array comprises a plurality of micro vortex generators, and resistance reduction of a turbulent boundary layer is realized by changing the configuration of the micro vortex generators; the friction force collecting module is installed on the side edge of the single-degree-of-freedom air floating platform and used for collecting the friction force of the friction force sensing flat plate. According to the technical scheme, passive drag reduction control over the turbulent boundary layer can be achieved.

Description

Technical Field

[0001] This invention belongs to the field of drag reduction technology, and in particular relates to an experimental device for drag reduction of turbulent boundary layer based on a micro vortex generator array. Background Technology

[0002] In transportation vehicles such as aircraft, ships, and automobiles, as well as industrial pipeline transportation, turbulent boundary layer friction drag is a crucial factor affecting the overall aerodynamics of the vehicle. As a significant component of total aerodynamic drag, wall friction drag can account for over 50% of the total drag of an aircraft under subsonic conditions and approximately one-third under supersonic conditions. However, turbulent flow intensifies with increasing velocity, and significant velocity fluctuations and complex vortex structures exist within the turbulent boundary layer at high Reynolds numbers. The shear stress induced by these vortices is the primary cause of wall friction drag. Therefore, effectively reducing friction drag is of great significance for reducing energy consumption and improving the transportation efficiency of the vehicle.

[0003] Existing drag reduction technologies for turbulent boundary layers can generally be divided into two main categories: passive control and active control. Active control methods (such as plasma actuators and pulsed jet arrays) require the injection of external energy or momentum, resulting in significant drag reduction but with complex structures. Passive control methods (such as vortex generators) generally rely on geometric structures to disturb the flow, offering advantages such as simple manufacturing processes, low cost, and no need for external energy, making them easier to apply in engineering. Vortex generators, as a typical passive control method, are small in size and easy to manufacture, demonstrating high convenience in both experimental research and engineering applications. Although the drag reduction effect of vortex generators is relatively small, accurately measuring their drag reduction, elucidating their drag reduction mechanism, and further exploring their drag reduction potential will be of great significance to meeting the drag reduction needs in transportation, industrial production, and other fields.

[0004] The geometric design of vortex generator drag reduction technology essentially involves setting up a raised structure of a certain height on the surface of the carrier. When the incoming flow passes through the vortex generator, an asymmetric pressure distribution is formed on its windward and leeward sides, resulting in additional drag, which may even increase drag. How to mitigate the influence of this additional drag and achieve net drag reduction is a key problem that urgently needs to be solved in current research on passive drag reduction in turbulent boundary layers. Summary of the Invention

[0005] The purpose of this invention is to provide an experimental device for drag reduction of turbulent boundary layer based on a micro vortex generator array, so as to solve the problems existing in the prior art.

[0006] To achieve the above objectives, this invention provides an experimental device for drag reduction in turbulent boundary layers based on a micro vortex generator array, comprising a single-degree-of-freedom air-float platform, a four-degree-of-freedom coarse-adjustment base, a friction force capture module, and a friction force acquisition module. The friction force capture module, the single-degree-of-freedom air-float platform, and the four-degree-of-freedom coarse-adjustment base are installed sequentially from top to bottom. The friction force capture module includes a friction force sensing plate and a micro vortex generator (MVG) array mounted above the friction force sensing plate. The micro vortex generator array includes several micro vortex generators, and drag reduction in the turbulent boundary layer is achieved by changing the configuration of the micro vortex generators. The friction force acquisition module is installed on the side of the single-degree-of-freedom air-float platform and is used to collect the friction force of the friction force sensing plate.

[0007] Optionally, the geometric parameters of the micro vortex generator include height, angle of attack, and lateral spacing.

[0008] Optionally, each micro vortex generator is mounted above the friction sensing plate via a corresponding mounting block.

[0009] Optionally, the arrangement of the micro vortex generator includes, but is not limited to, co-rotating blade arrays, counter-rotating blade arrays, and "high-low-high-low" type blade arrays.

[0010] Optionally, the shape of the micro vortex generator includes, but is not limited to, triangles, rectangles, trapezoids, rotating trapezoids, wedges, and ramps.

[0011] Optionally, the material of the micro vortex generator includes, but is not limited to, metal, resin, and plastic molding materials.

[0012] Optionally, the friction force acquisition module includes a lever mechanism and a force sensor. The force sensor is installed on the side of the single-degree-of-freedom air-bearing platform. One end of the lever mechanism is connected to the friction force sensing plate, and the other end is connected to the force sensor. The frictional resistance generated between the friction force sensing plate and the wind tunnel wall is transmitted to the force sensor through the lever mechanism.

[0013] Optionally, it also includes an air filter and an air compressor, with one end of the air filter connected to the air compressor via an air pipe and the other end connected to the single-degree-of-freedom air flotation platform via an air pipe.

[0014] The technical effects of this invention are as follows: This invention provides an experimental device for drag reduction in turbulent boundary layers based on a micro vortex generator array. The array uses MVGs to generate similar flow-directed vortex structures to achieve drag reduction control of the turbulent boundary layer. This invention belongs to passive drag reduction technology, requiring no external energy input or complex maintenance equipment, and therefore possesses good engineering applicability.

[0015] This invention experimentally discovers for the first time that MVG arrays are an effective device for reducing frictional drag in turbulent boundary layers. They can generate large-scale streamwise vortices (LSSVs) rotating in the same (or opposite) direction. These LSSVs not only reduce wall friction but also achieve a drag reduction exceeding the drag increase caused by pressure differential drag or additional drag induced by MVGs, thus achieving net drag reduction. It is noteworthy that, due to the presence of additional drag, no researchers have yet achieved net drag reduction of vortex generators in zero-pressure gradient turbulent boundary layers through wind tunnel experiments, nor have they measured the net drag reduction of vortex generators through wind tunnel experiments. Thanks to the team's previously innovative ultra-high precision balance for measuring turbulent boundary layer friction, this invention measured the wall friction of turbulent boundary layers under the control of 486 MVG arrays. Each MVG array contains different micro-vortex generator shapes, height h, angle of attack α, and lateral spacing. Based on the measurement results, this invention discovered in wind tunnel experiments that: at a Reynolds number based on momentum thickness of... Under operating conditions, MVGs adopt a triangular blade shape and a co-rotating array, with height h / displacement thickness. =0.2, angle of attack α=10°, spacing When h=5, the experiment achieved a drag reduction DR=-4.3%, demonstrating the feasibility of using MVG arrays to reduce wall friction in turbulent boundary layers. (Where, drag reduction is defined as...) , F is the turbulent boundary layer wall friction resistance (Pa) after MVGs array control. ref It is the turbulent boundary layer wall friction resistance (Pa) before MVGs array control. A negative sign indicates drag reduction, and a positive sign indicates drag increase.

[0016] This invention also discovered in wind tunnel experiments that, with optimal MVG array parameters (i.e., micro vortex generator shape, height h, angle of attack α, and lateral spacing), Under certain conditions, the drag reduction effect of the MVGs array can be further improved with the increase of Reynolds number (or wind speed). Experimental results show that the drag reduction DR is related to the height h, angle of attack α, and lateral spacing of the micro-vortex generator. The intensity and flow-direction persistence of LSSVs induced by MVGs increase inversely with increasing Reynolds number. The experiment employed three Reynolds number models based on momentum thickness. , The studies were conducted separately, with the MVG arrays using the same angle of attack α=10° and spacing... When / h=5, only h / Net drag reduction can be achieved when the value is ≤0.2; when MVG arrays use the same spacing / h=5, height h / When α = 0.2, DR achieves maximum drag reduction at an angle of attack α = 10°; when the MVGs array uses the same angle of attack α = 10°, the height h / When = 0.2, DR at the spacing Maximum drag reduction is achieved when h=5. Furthermore, when the MVG array adopts the optimal configuration, i.e., height h / =0.2, angle of attack α=10°, spacing When / h=5, the Reynolds number is Under the operating conditions, the experiment achieved maximum drag reduction DR=-0.3%, DR=-4.0%, and DR=-4.3%, respectively, which indicates the potential of MVGs arrays in engineering applications at high Reynolds numbers.

[0017] Inspired by the drag reduction mechanism of large-scale flow-oriented vortices generated by plasma exciters, this invention proposes using MVG arrays to generate large-scale flow-oriented vortices to stabilize strip structures, ultimately achieving drag reduction of turbulent boundary layer wall friction. The large-scale flow-oriented vortices generated by the MVG array can effectively reconstruct the near-wall ordered structure, making it more stable and reducing bursts and near-wall downsweep motions, thereby significantly reducing wall friction. The MVG array drag reduction method is a passive drag reduction approach, requiring no additional energy input or complex external maintenance equipment, making it easy to apply in engineering. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a side view of the experimental device for reducing frictional drag in turbulent boundary layer based on a micro vortex generator array, as described in an embodiment of the present invention. Figure 2 This is a top view of the experimental device for reducing frictional drag in turbulent boundary layer based on a micro vortex generator array, as described in an embodiment of the present invention. Figure 3 This is a schematic diagram of the turbulent boundary layer friction resistance measurement balance system based on a micro vortex generator array in an embodiment of the present invention; Figure 4 This is a schematic diagram of the configuration of the micro vortex generator in an embodiment of the present invention.

[0020] Labeling Explanation: 1. Friction Force Capture Module; 101. Friction Force Sensing Plate; 102. Outer Bushing; 103. Support Rod; 2. Micro Vortex Generator Array; 201. Micro Vortex Generator; 3. Single Degree of Freedom Air Flotation Platform; 301. Air Pipe; 302. Air Filter; 303. Air Compressor; 4. Horizontal Fine-tuning Base; 5. Four Degrees of Freedom Coarse-tuning Base; 6. Friction Force Amplification and Acquisition Module; 601. Force Sensor; 602. Lever Mechanism; 7. Wind Tunnel Wall; 8. Disturbance Pin Strip. Detailed Implementation

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

[0022] To facilitate understanding of the present invention, a more comprehensive description of the invention will be given below with reference to the accompanying drawings, and several embodiments of the invention will be provided. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of the invention will be more thorough and complete.

[0023] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only. The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0025] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments. Example

[0026] like Figures 1-4 As shown, this embodiment provides an experimental device for drag reduction of turbulent boundary layer based on a micro vortex generator array, including a single-degree-of-freedom air-float platform 3, a four-degree-of-freedom coarse-adjustment base 5, a friction force capture module 1, and a friction force acquisition module. The friction force capture module 1, the single-degree-of-freedom air-float platform 3, and the four-degree-of-freedom coarse-adjustment base 5 are installed sequentially from top to bottom. The friction force capture module 1 includes a friction force sensing plate 101 and a micro vortex generator array 2 installed above the friction force sensing plate 101. The micro vortex generator array 2 includes several micro vortex generators 201. The vortex generators 201 are in contact with the single-degree-of-freedom air-float platform 3. There are gaps around the single-degree-of-freedom air-float platform 3 and the bottom wall of the wind tunnel. The gaps need to be controlled at about 200 micrometers. The drag reduction of the turbulent boundary layer is achieved by changing the configuration of the micro vortex generators 201. The friction force acquisition module is installed on the side of the single-degree-of-freedom air-float platform 3 and is used to collect the friction force of the friction force sensing plate 101.

[0027] Existing vortex generator drag reduction technologies are primarily limited by the additional drag they introduce. MVG array drag reduction technology involves creating raised physical geometric structures on the surface of an object. When fluid flows through these structures, it generates LSSVs (Layered Surface Stabilizers) to reduce wall friction. However, this also generates additional drag. This additional drag is related to the geometric parameters of the MVGs (such as height h, angle of attack α, and lateral spacing). The drag is closely related to the resistance of the wall surface, especially under high Reynolds number conditions, where even small changes in geometric parameters can lead to drastically different drag-increasing effects. Therefore, this embodiment aims to suppress the drag-increasing effect of additional resistance by optimizing the geometric parameters of the MVGs array, thereby achieving not only net drag reduction but also improving the drag reduction performance of wall friction resistance.

[0028] The drag reduction method for turbulent boundary layer based on MVG arrays provided in this embodiment not only achieves net drag reduction, but also reveals for the first time the drag reduction potential of this technology under high Reynolds number conditions. Experimental results using this method in conjunction with a turbulent boundary layer friction drag measurement balance system demonstrate that, at Reynolds numbers based on momentum boundary layer thickness... When the value is 20, DR = -0.3%; When the value is 30, DR = -4.0%; At a Reynolds number of 40, the drag reduction (DR) is -4.3%. This trend indicates that the drag reduction performance of MVGs significantly improves with increasing Reynolds number (or incoming flow velocity). Currently, most experimental studies on MVG control of turbulent boundary layers are limited to low Reynolds number conditions, and may even lead to increased drag due to the additional drag introduced by MVGs. In contrast, the turbulent boundary layer drag reduction method based on MVG arrays proposed in this embodiment has, for the first time in the world, been discovered in wind tunnel experiments: the large-scale flow-directed vortices generated by the MVG array not only suppress the drag-increasing effect caused by additional drag, achieving net drag reduction, but also, with increasing Reynolds number, the intensity of the large-scale flow-directed vortices generated by the MVG array increases, and the persistence of these flow-directed vortices along the flow direction is further enhanced.

[0029] Currently, existing literature does not elucidate how vortex generators achieve precise control over the structural scale of turbulent boundary layers, nor does it provide a systematic study on the drag reduction performance of MVG arrays under high Reynolds number conditions. Inspired by the mechanism of drag reduction achieved by plasma exciters through the generation of large-scale flow-oriented vortices, this embodiment proposes that the large-scale flow-oriented vortices generated by the MVG array reconstruct the near-wall quasi-ordered structure, significantly increasing the turbulent kinetic energy dissipation rate. This leads to a reduction in sudden events and a more uniform shear stress distribution in the turbulent boundary layer, which is beneficial for reducing wall friction drag. Specifically: First, the MVG array induces a series of counter- or co-rotating flow-oriented vortex structures in the turbulent boundary layer. These vortex structures alter the original wall vortex distribution. Under average shear, the vortex lines are stretched and tilted, thereby enhancing vortex dissipation in the outer boundary layer and establishing a vortex flux balance mechanism that can suppress wall vortex generation. Secondly, the aforementioned eddy redistribution process disrupts the self-sustaining cycle of the original pseudo-order structure (such as low-speed stripes and quasi-flow vortices) in the near-wall region and reconstructs a more stable pseudo-order organization, effectively reducing sudden events and near-wall downsweep motion, and ultimately reducing wall friction drag.

[0030] The turbulent boundary layer drag reduction experimental apparatus provided in this embodiment specifically includes: like Figures 1-2 As shown, the micro vortex generator array 2 is part of the friction capture module 1 and is used in conjunction with the friction sensing plate 101.

[0031] like Figure 3 The micro vortex generator array 2 shown has arrays spaced L apart. The array contains multiple micro vortex generators 201. Figure 3 The micro vortex generator 201 shown adopts an array of blades rotating in the same direction.

[0032] Alternatively, the micro vortex generator array 2 can be directly embedded or welded to the friction sensing plate 101. Or, the micro vortex generator array 2 can be directly embedded or welded to a mounting block, which is then fixed to the friction sensing plate 101.

[0033] This embodiment achieves drag reduction by synchronously or individually changing the geometric parameters of the micro vortex generator, and provides a measuring balance to measure the frictional resistance experienced by the micro vortex generator control area on the wall of the friction sensing plate 101 before and after control.

[0034] The geometric parameters of the micro vortex generator 201 include, but are not limited to, height h, thickness w, angle of attack α formed with the free flow direction (x direction), and lateral spacing between adjacent micro vortex generators 201. Length of triangle wait.

[0035] Implementable, refer to Figure 4 As shown, the micro vortex generator array 2 includes, but is not limited to, blade arrays composed of blades rotating in the same direction, blades rotating in opposite directions, and "high-low-high-low" type blades (i.e., the height h of adjacent micro vortex generators 201 is not exactly the same).

[0036] The shape of the micro vortex generator 201 may include, but is not limited to, triangles, rectangles, trapezoids, rotating trapezoids, wedges, ramps, etc.

[0037] It is feasible that the material of the micro vortex generator 201 includes, but is not limited to, metals (steel, aluminum alloy, tungsten alloy, etc.), resin and other plastic molding materials.

[0038] In this embodiment, an air filter 302 and an air compressor 303 are also provided. One end of the air filter 302 is connected to the air compressor 303 through an air pipe, and the other end is connected to the single-degree-of-freedom air flotation platform through an air pipe.

[0039] refer to Figure 1 As shown, the drag reduction experiment implemented by the friction force capture module 1 in conjunction with the single-degree-of-freedom air-float platform 3 illustrates the following: Wind tunnel walls 7 are provided on both sides of the top wall of the friction force sensing plate 101. The wind tunnel walls 7 and the top wall of the friction force sensing plate 101 are on the same plane, and a micro-vortex generator array appears above the control area of ​​the friction force sensing plate 101. Furthermore, refer to... Figures 1-3As shown, the single-degree-of-freedom air-bearing platform 3 is based on planar air-bearing bearing technology, enabling the friction-sensing plate 101 to slide frictionlessly in the horizontal plane. A micro-vortex generator array 2 is placed on and fixedly connected to the friction-sensing plate 101. This allows the frictional resistance acting on the top wall of the friction-sensing plate 101 to be transmitted to the force sensor 601 via a lever mechanism 602, enabling frictional force measurement to calculate the drag reduction after control. A 0.2mm gap is required between the force-sensing plane and the wind tunnel wall to provide the necessary displacement for measurement. The friction-sensing plate 101 and the planar air-bearing bearing, among other equipment, need to be sealed and connected only to the wind tunnel wall. This ensures that the interior of the single-degree-of-freedom air-bearing platform 3 is under the same pressure as the interior of the wind tunnel, eliminating measurement errors caused by pressure differences.

[0040] The drag reduction in the control area of ​​the friction sensing plate 101 is calculated using the following formula:

[0041] in, The frictional resistance (Pa) of the wall frictional sensing plate 101 in the turbulent boundary layer after being controlled by the micro vortex generator array 2; F ref The micro vortex generator array 2 controls the wall friction resistance (Pa) of the friction sensing plate 101 in the turbulent boundary layer; a negative DR indicates drag reduction, and a positive DR indicates drag increase.

[0042] The above experiments employed three Reynolds numbers based on momentum thickness (…). , =20; , =30; , =40) was studied, when MVGs array 2 used the same angle of attack α=10°, and the spacing was 40) When / h=5, only h / Net drag reduction can be achieved when the value is ≤0.2; when the MVGs array 2 uses the same spacing / h=5, height h / When α = 0.2, DR achieves maximum drag reduction at an angle of attack α = 10°; when MVGs array 2 uses the same angle of attack α = 10°, the height h / When = 0.2, DR at the spacing The maximum drag reduction is achieved when h=5. Furthermore, when the MVGs array 2 adopts the optimal configuration, i.e., height h / =0.2, angle of attack α=10°, spacing When / h=5, the Reynolds number is Under the operating conditions, the experiment can achieve maximum drag reduction of DR=-0.3%, DR=-4.0%, and DR=-4.3%, respectively.

[0043] The force measurement experiment results show that the drag reduction DR is related to the height h, angle of attack α, and lateral spacing of the micro vortex generator 201. Inversely proportional. The drag reduction DR is related to the Reynolds number. This relationship, being directly proportional, makes it possible to apply micro-vortex generators to engineering applications at high Reynolds numbers. Particle image velocimetry (PIV) results show that the triangular micro-vortex generator 201 can induce large-scale flow-directed vortices. These large-scale flow-directed vortices can achieve drag reduction due to wall friction, exceeding the drag increase effect caused by the geometry of the micro-vortex generator itself, thus achieving net drag reduction. Furthermore, the intensity of these large-scale flow-directed vortices increases with increasing Reynolds number, and their persistence along the flow direction also increases with increasing Reynolds number.

[0044] Currently, in the limited number of experiments on turbulent boundary layer MVG control, all existing MVG control studies have been conducted under low Reynolds number conditions. Due to the presence of additional drag, no researchers have yet achieved net drag reduction of vortex generators in zero-pressure gradient turbulent boundary layers through wind tunnel experiments, nor have they measured the net drag reduction of vortex generators through wind tunnel experiments. Therefore, the aforementioned drag reduction method based on MVG arrays for turbulent boundary layers weakens the additional drag caused by the geometry of the MVGs themselves, improves the drag reduction performance of wall friction drag, achieves net drag reduction, and points out the potential of MVG array drag reduction under high Reynolds number conditions.

[0045] Furthermore, the aforementioned drag reduction method for turbulent boundary layer based on MVG arrays reveals that the large-scale flow-oriented vortices generated by the MVG arrays play a role in stabilizing the stripe structure. The physical mechanism of drag reduction using MVG arrays essentially stems from the regulation of vortex transport processes within the turbulent boundary layer. First, the MVG array induces flow-oriented vortex structures rotating in opposite or the same direction within the turbulent boundary layer. This flow-oriented vortex structure alters the wall vortex distribution before control. Under mean shear, the stretching and tilting effects of vortex lines enhance the vortex dissipation rate in the outer boundary layer, thereby establishing a vortex flux balance mechanism that suppresses wall vortex sources. Second, this vortex redistribution disrupts the self-sustaining cycle of the near-wall turbulent boundary layer pseudo-ordered structures (such as low-velocity stripes and quasi-flow-oriented vortices) and effectively reorganizes the near-wall pseudo-ordered structures, making them more stable, reducing sudden bursts and near-wall sweep motions, thereby reducing wall friction drag.

[0046] The above description is merely a preferred embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An experimental device for drag reduction in turbulent boundary layers based on a micro-vortex generator array, characterized in that, The system includes a single-degree-of-freedom air-float platform (3), a four-degree-of-freedom coarse-adjustment base (5), a friction force capture module (1), and a friction force acquisition module. The friction force capture module (1), the single-degree-of-freedom air-float platform (3), and the four-degree-of-freedom coarse-adjustment base (5) are installed sequentially from top to bottom. The friction force capture module (1) includes a friction force sensing plate (101) and a micro vortex generator array (2) installed above the friction force sensing plate (101). The micro vortex generator array (2) includes several micro vortex generators (201). The drag reduction of the turbulent boundary layer is achieved by changing the configuration of the micro vortex generators (201). The friction force acquisition module is installed on the side of the single-degree-of-freedom air-float platform (3) and is used to collect the friction force of the friction force sensing plate (101).

2. The experimental device for drag reduction of turbulent boundary layer based on a micro vortex generator array according to claim 1, characterized in that, The geometric parameters of the micro vortex generator (201) include height, angle of attack, and lateral spacing.

3. The experimental device for drag reduction of turbulent boundary layer based on a micro vortex generator array according to claim 1, characterized in that, Each micro vortex generator (201) is mounted on top of the friction sensing plate (101) via a corresponding mounting block.

4. The experimental device for drag reduction of turbulent boundary layer based on a micro vortex generator array according to claim 1, characterized in that, The arrangement of the micro vortex generator (201) includes, but is not limited to, co-rotating blade arrays, counter-rotating blade arrays, and high-low-high-low blade arrays.

5. The experimental device for drag reduction of turbulent boundary layer based on a micro vortex generator array according to claim 1, characterized in that, The shape of the micro vortex generator (201) includes, but is not limited to, triangle, rectangle, trapezoid, rotating trapezoid, wedge and ramp.

6. The experimental device for drag reduction of turbulent boundary layer based on a micro vortex generator array according to claim 1, characterized in that, The material of the micro vortex generator (201) includes, but is not limited to, metal, resin and plastic molding materials.

7. The experimental device for drag reduction of turbulent boundary layer based on a micro vortex generator array according to claim 1, characterized in that, The friction force acquisition module includes a lever mechanism (602) and a force sensor (601). The force sensor (601) is installed on the side of the single-degree-of-freedom air-float platform (3). One end of the lever mechanism (602) is connected to the friction force sensing plate (101), and the other end is connected to the force sensor (601). The frictional resistance generated between the friction force sensing plate (101) and the wind tunnel wall (7) is transmitted to the force sensor (601) through the lever mechanism (602).

8. The experimental device for drag reduction of turbulent boundary layer based on a micro vortex generator array according to claim 1, characterized in that, It also includes an air filter (302) and an air compressor (303), one end of which is connected to the air compressor (303) via an air pipe (301), and the other end is connected to the single-degree-of-freedom air flotation platform (3) via an air pipe (301).

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