A wall confinement effect adjustable flow control experiment system and method

Abstract

The application discloses a flow control experiment system and method with adjustable wall restriction effect, and belongs to the technical field of hydrodynamic experiments and the research field of active flow control.The system comprises a water tank module, an active flow control module for controlling rotation of a measured blunt body in the water tank module, a horizontal sliding module for controlling movement of the measured blunt body in the water tank module, and a state detection module for monitoring and controlling an experiment state.The water tank module comprises two wall restriction effect adjustable water tank bodies, and adaptive adjustment of a blockage ratio is achieved by adjusting the distance between the two walls.The application aims to adjust the distance between the two side walls in a larger parameter range, to explore the influence of changes of a Reynolds number and a blockage ratio on control efficiency by means of real-time feedback active flow control, to better utilize the blockage ratio, and to finally realize strengthening of fluid mixing and heat transfer or collection of vibration energy.

Description

Technical Field

[0001] This invention belongs to the fields of hydrodynamic experimental technology and active flow control research, specifically relating to a flow control experimental system and method with adjustable wall confinement effect. Background Technology

[0002] When fluids flow through a bluff body, complex flow phenomena occur, including flow separation, eddy generation, and shedding. Cylinders are a typical bluff body structure, and these problems have been observed in both nature and industrial applications, attracting significant academic attention. When the eddy shedding frequency matches the structural frequency, eddy-induced vibration (VIV) may occur. This can lead to surface wear, material fatigue, and creep in the cylinder, ultimately causing structural failure. When the blockage ratio D / W (the ratio of the cylinder's diameter (D) to the distance between the two side walls (W)) is large, the interaction between the shear layer generated on the side walls and the shear layer separated from the cylinder enhances turbulent mixing in the wake, accompanied by a surge in lift and drag. Therefore, engineering applications require effective control methods to reduce the adverse effects of bluff body eddy shedding.

[0003] Flow control methods are generally divided into passive control and active control. Passive control methods do not require external energy input to maintain the control process. For example, a prior art method for controlling cylindrical flow with two symmetrical flexible plates reduces lift and drag by adjusting the stiffness and connection angle of the flexible plates. In contrast, active control methods require external energy input and can be designed with appropriate control laws based on the current experimental environment. Therefore, active control offers greater controllability and adjustability.

[0004] Current experimental setups for active flow control all have fixed side walls, limiting their application to unconstrained (sufficiently far side walls, low blockage ratio) or constrained (sufficiently close side walls, high blockage ratio) scenarios. This restricts research on the blockage ratio itself. However, fully utilizing the blockage ratio holds promise for enhancing fluid mixing, heat transfer, and vibration energy harvesting. Therefore, there is an urgent need to develop an active flow control experimental platform with an adjustable blockage ratio to investigate the gains and losses associated with this parameter and achieve the desired objectives through active flow control. Summary of the Invention

[0005] The technical problem to be solved:

[0006] To avoid the shortcomings of existing technologies, this invention provides a flow control experimental system and method with adjustable wall confinement effect. It aims to adjust the distance between the two side walls within a wider parameter range, and to explore the impact of changes in Reynolds number and blockage ratio on control efficiency through real-time feedback active flow control, thereby making better use of the blockage ratio and ultimately achieving enhanced fluid mixing and heat transfer or vibration energy collection.

[0007] The technical solution of the present invention is: a flow control experimental system with adjustable wall confinement effect, including a water tank module, an active flow control module for controlling the rotation of the test bluff body within the water tank module, a horizontal sliding module for controlling the movement of the test bluff body within the water tank module, and a state detection module for monitoring and controlling the experimental state.

[0008] The water tank module includes a water tank body with adjustable wall confinement effect, and the blocking ratio is adaptively adjusted by adjusting the distance between the two walls.

[0009] A further technical solution of the present invention is: the water tank body with adjustable two-wall constraint effect includes a water tank body, two side plates located therein, and a lateral moving mechanism for driving the two side plates to move in opposite directions; the two side plates are parallel to each other and parallel to the water flow direction in the water tank body, and the lateral moving mechanism controls the two side plates to move in opposite directions perpendicular to the water flow, thereby adjusting the distance between the two side plates.

[0010] A further technical solution of the present invention is: the water tank module further includes a water tank base with a frame structure, and the water tank body is embedded in the water tank base; the lateral movement mechanism is installed on the water tank base and includes a lateral lead screw and a lateral servo motor. The lateral lead screw passes through the reverse threaded holes on the two side plates in sequence. The lateral servo motor drives the lead screw to rotate, converting the rotational motion of the lateral lead screw into the linear motion of the two side plates along the lateral lead screw, so that the two side plates move away from each other or closer together.

[0011] A further technical solution of the present invention is: a hanging ear is provided on the top of the side plate along the extension direction of the plate surface, and a threaded hole is opened on the hanging ear to cooperate with the transverse lead screw, and the threaded holes of the two side plates have opposite thread directions.

[0012] A further technical solution of the present invention is: the active flow control module includes a fixed bracket, a flow control servo motor, and a retractable rectifier net. The fixed bracket is mounted on the water tank base, on which the flow control servo motor is installed, and on both sides thereare retractable rectifier nets to break up the eddies left over from the previous experiment.

[0013] The output end of the flow control servo motor is connected to the blunt body under test via a coupling, and the blunt body under test is suspended between the two side plates inside the water tank body.

[0014] A further technical solution of the present invention is that the distance between the bottom surface of the blunt object being tested and the bottom surface of the water tank body is less than 5cm, which can reduce the tip effect of the blunt object being tested.

[0015] A further technical solution of the present invention is as follows: the horizontal sliding module includes two sets of identical horizontal slide rails arranged symmetrically, which are respectively installed on opposite sides of the water tank base via the water tank guide rail base; the horizontal slide rail includes a horizontal lead screw and a slider, with two sliders respectively installed on both sides of the fixed bracket; the horizontal lead screw is driven to rotate by a horizontal power component, and the rotational motion of the horizontal lead screw is converted into the linear motion of the fixed bracket along the axis of the horizontal lead screw driven by the slider, thereby driving the blunt object being measured to move in the water tank.

[0016] A further technical solution of the present invention is: the horizontal sliding module further includes a horizontal sliding rail, which is a closed structure and is installed on the water tank guide rail base through a horizontal sliding rail connecting plate. A horizontal lead screw is rotatably installed inside the rail for stable transmission, guiding movement and isolating external dust; and a limit sensor is installed at the end of the horizontal sliding rail to prevent the movement from exceeding the specified stroke.

[0017] A further technical solution of the present invention is as follows: the state detection module includes a velocity sensor, a vibration collector, a distance sensor, a motion controller, a feedback device, and a display screen. The velocity sensor and the vibration collector are mounted on the active flow control module, and the distance sensor is mounted on the inner wall of both side plates. The input end of the feedback device is connected to the velocity sensor, the vibration collector, and the distance sensor to receive signals, and its output end is connected to the display screen and the motion controller, respectively. The motion controller receives the feedback signal and outputs commands to the active flow control module and the horizontal sliding module to realize the motion control of the measured blunt body; it also outputs commands to the water tank module to realize the adjustment of the limiting effect of the two walls.

[0018] An experimental method for flow control with adjustable wall confinement effect, the specific steps of which are as follows:

[0019] Step 1: Pour water into the water tank body, controlling the water level at 4 / 5 of the height of the water tank body; then add an appropriate amount of tracer particles to the water tank;

[0020] Step 2: Input the experimental parameters into the controller. The experimental parameters include the blocking ratio, Reynolds number, and control law.

[0021] Step 3: Based on the blocking ratio requirement received by the feedback device, the motion controller controls the horizontal servo motor to work, so as to adjust the distance between the two side plates inside the water tank body; at the same time, the distance sensor feeds back the current distance between the two side plates, and the closed-loop feedback is sent to the motion controller to adaptively adjust the blocking ratio to achieve the expected blocking ratio.

[0022] Step 4: Based on the Reynolds number requirement received by the feedback device, the motion controller controls the horizontal sliding module to move the tested blunt body stably between the two side plates; the current movement speed and vibration are fed back to the motion controller through the speed sensor and vibration acquisition device to detect the current motion state;

[0023] Step 5: Obtain the current flow state using particle image velocimetry (PEV) technology;

[0024] Step 6: Use the current flow state as the input to the motion controller, which controls the active flow control module to drive the measured blunt body to rotate and execute an effective control law to enhance turbulent mixing in the wake or to harvest energy based on vortex-induced vibration.

[0025] Step 7: Stretch the retractable rectifier net into the water tank body, and the motion controller sends a return signal to clear the residual vortex in the water tank body.

[0026] Step 8: Repeat steps 2 through 7 to explore a wider parameter space.

[0027] Beneficial effects

[0028] The beneficial effects of this invention are as follows: This invention focuses on the research of experimental platforms for wall-confined flow, which has significant implications for engineering applications. On the one hand, an increase in the blockage ratio may lead to a significant increase in the hydrodynamic forces (flow resistance and lift perpendicular to the incoming flow) acting on the confined cylinder. Appropriate active flow control can facilitate energy harvesting based on vortex-induced vibrations. On the other hand, the shear layer separated from the sidewalls interacts with the shear layer separated from the cylinder, thereby enhancing turbulent mixing in the wake. Active flow control can enhance the heat transfer effect in the wake.

[0029] The lead screw guide rail used in this invention has good low-speed stability, thus allowing for the exploration of a smaller Reynolds number range (100-1000), facilitating interactive research with numerical simulations.

[0030] This invention, by adding a lateral moving mechanism to the sidewalls, allows for free adjustment of the wall spacing, thereby exploring the effect of blockage ratio on bluff body flow within a wide parameter range. Compared to previous experimental platforms, the advantage of this invention is that it can investigate both low-blockage-ratio and high-blockage-ratio bluff body flow environments. Furthermore, it is equipped with an active flow control system, which can better utilize high-blockage-ratio environments to achieve favorable control. Experimental results show the following:

[0031]

[0032] The table shows that when the blocking ratio increases from 1 / 20 to 1 / 4, the average resistance of the cylinder... and pulsating lift (C′) L The confinement effect adjustable flow control experimental platform designed in this invention can flexibly explore the influence of this parameter over a wider range, and make full use of these fluid forces (drag and lift) to achieve efficient energy harvesting and release. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of an experimental system for flow control with adjustable wall confinement effect according to the present invention.

[0034] Figure 2 This is a partially enlarged schematic diagram of the lateral movement mechanism described in this invention.

[0035] Figure 3 This is a partially enlarged schematic diagram of the horizontal sliding module described in this invention.

[0036] Figure 4 This is a partially enlarged schematic diagram of the active flow control module described in this invention.

[0037] Figure 5 This is a connection diagram of the state detection module described in this invention.

[0038] Figure 6 This is a schematic diagram of the particle image velocimetry technology described in this invention.

[0039] Explanation of reference numerals in the attached drawings: 1-Water tank base, 2-Limit sensor, 3-First horizontal slide rail, 4-First slider, 5-Vibration collector, 6-Fixed bracket, 7-Flow control servo motor, 8-Water tank guide rail base, 9-First horizontal power assembly, 10-Horizontal servo motor, 11-Second horizontal power assembly, 12-Second horizontal slide rail, 13-Horizontal lead screw, 14-Horizontal movement mechanism, 15-Velocity sensor, 16-Second slider, 17-Vertical coupling, 18-Cylinder (blunt body under test), 19-Retractable rectifier net, 20-Water tank body, 21-Water tank side plate; 301-Horizontal slide rail, 302-Horizontal lead screw, 303-Horizontal slide rail connecting plate; 901-Horizontal servo motor, 902-Horizontal coupling; 141-First water tank side plate hanging lug, 142-Second water tank side plate hanging lug, 143-Distance sensor. Detailed Implementation

[0040] The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the invention, and should not be construed as limiting the invention.

[0041] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0042] Existing technologies can only explore unconstrained (sufficiently far sidewalls, low blockage ratio) or constrained (sufficiently close sidewalls, high blockage ratio) flow conditions, limiting the study of blockage ratio. This invention proposes a flow control experimental system and method with adjustable wall confinement effects. This system is an intelligent flow control experimental platform that suppresses hydrodynamic fluctuations or enhances turbulent heat transfer through cylindrical rotation, and its blockage ratio can be continuously adjusted. The specific technical solution is as follows:

[0043] The aforementioned flow control experimental system with adjustable wall confinement effect includes a water tank module, a horizontal sliding module, an active flow control module, and a state detection module. The water tank module comprises a water tank body and a water tank base. The horizontal sliding module includes a first and second horizontal sliding rail symmetrically arranged along the center of the water tank, a first horizontal power component, and a second horizontal power component. The two sets of horizontal sliding modules are mounted on opposite sides above the water tank base. The active flow control module body is slidably connected to the first and second horizontal sliding rails. The bluff body under test is fixed at the center of the active flow control module. The state detection module is mounted on a fixed support of the active flow control module and interacts with both the horizontal sliding module and the water tank module.

[0044] The water tank module includes a water tank base, a water tank body with adjustable wall confinement effect, two side plates located within the water tank body, and a lateral moving mechanism that drives the side plates to move in opposite directions. The side plates are parallel to each other and parallel to the water flow direction within the water tank body. The water tank body is embedded in the water tank base. The lateral moving mechanism is mounted on the water tank base and includes a lateral lead screw and a lateral servo motor. The lateral lead screw passes through reverse threaded holes on the side plates in sequence. The lateral servo motor drives the lead screw to rotate, converting the rotational motion of the lateral lead screw into linear motion of the side plates along the lateral lead screw, causing the side plates to move away from or towards each other. Each of the two movable side plates has two pairs of lugs with internal threads. The threads of the two pairs of lugs symmetrical along the center line are in opposite directions. When the lateral lead screw rotates clockwise or counterclockwise, the two movable side plates will move inward or outward simultaneously. The water tank body with adjustable wall confinement effect can detect the current vertical distance between the two walls based on a distance sensor. If a deviation between the set value and the actual value is detected, the motor inside the side wall will drive the horizontal lead screw structure to adjust the distance between the two side walls.

[0045] The horizontal sliding module includes a horizontal slide rail, a horizontal sliding power system, a water tank guide rail base, and limit sensors. The horizontal slide rail comprises a horizontal slide track, a horizontal lead screw, and a slider. The horizontal lead screw is located within the horizontal slide rail. The fully sealed horizontal slide rail provides stable transmission, guides movement, and isolates external dust. The horizontal sliding power system is driven by a servo motor, whose drive shaft is connected to the horizontal lead screw via a rigid coupling. Driving the horizontal lead screw causes the slider to move axially along the lead screw. Two sets of horizontal slide rails and the horizontal sliding power system are symmetrically fixed to the top of the water tank guide rail base via horizontal slide rail connecting plates. The water tank guide rail base is installed on both sides above the water tank base. The limit sensors are located at the ends of the horizontal slide rails to prevent movement from exceeding the specified stroke.

[0046] The active flow control module includes a fixed bracket, a retractable rectifier net, and an active flow control component. In the active flow control component, the cylinder under test is connected to the output shaft of a flow control servo motor via a rigid coupling. The motion of the flow control servo motor can be transmitted to the cylinder under test, thus achieving active control. The end of the cylinder under test is freely suspended, and the distance between the bottom surface of the cylinder and the bottom of the water tank is less than 5 cm to reduce the tip effect of the cylinder. The fixed bracket is connected to sliders on both sides and is perpendicular to the horizontal slide rails at both ends. A horizontal lead screw rotates, driving the sliders and the fixed bracket to slide along the horizontal slide rails. Retractable rectifier nets are installed on both sides of the fixed bracket to break up eddies remaining from the previous experiment.

[0047] The state detection module includes a speed sensor, a vibration collector, a distance sensor, a motion controller, a feedback unit, and a display screen. The input of the feedback unit is connected to the speed sensor, vibration collector, limit sensor, and distance sensor of the active flow control module, and its output is connected to the display screen. The input of the motion controller is connected to the feedback unit to receive feedback signals from the system, and its output is connected to the horizontal sliding module and the active flow control module to execute commands given by the operator.

[0048] This invention aims to adjust the distance between the two side walls within a wider parameter range, and to explore the impact of changes in Reynolds number and blockage ratio on control efficiency through real-time feedback active flow control, thereby making better use of the blockage ratio and ultimately achieving enhanced fluid mixing and heat transfer or vibration energy collection.

[0049] Example:

[0050] The present invention will be further described below with reference to the accompanying drawings and specific embodiments: This embodiment is implemented based on the technical solution of the present invention, and provides detailed implementation methods and specific operating procedures, but the scope of protection of the present invention is not limited to the following embodiments. The total length of this experimental device is 3500mm, the total height is 1000mm, and the total width is 800mm. The assembly of each component is as follows: Figure 1 As shown.

[0051] The wall-constraint effect adjustable flow control experimental system of this embodiment includes a water tank module, a horizontal sliding module, an active flow control module, and a state detection module. The water tank module includes a water tank body 20 and a water tank base 1. The horizontal sliding module includes a first horizontal slide rail 3 and a second horizontal slide rail 12 symmetrically arranged along the center of the water tank, a first horizontal power component 9, and a second horizontal power component 11. The horizontal sliding module is mounted on a water tank guide rail base 8 above the water tank base 1. The active flow control module body is connected to the first horizontal slide rail 3 and the second horizontal slide rail 12 respectively. The cylinder 18 under test is fixed at the center of the active flow control module. The state detection module is mounted on a fixed bracket 6 of the active flow control module and interacts with both the horizontal sliding module and the water tank module.

[0052] The water tank module includes: a water tank base 1 and an adjustable water tank model with water tank side plates 21. The adjustable water tank model with water tank side plates 21 can detect the vertical distance of the current water tank side plates 21 based on feedback from the distance sensor 143. A transverse screw structure 14 driving the movement of the water tank side plates 21 is connected to the side wall of the water tank base 1. The two movable water tank side plates 21 each have two pairs of lugs 141 and 142, each with internal threads. The threads of the two pairs of lugs 141 and 142, symmetrical along the center line, are opposite in direction. When the screw rotates clockwise or counterclockwise, the two movable side walls move outward or inward simultaneously. If a deviation between the set value and the actual value is detected, a transverse servo motor 10 inside the side wall will drive the transverse movement mechanism 14, thereby adjusting the distance between the two side walls. Figure 2 As shown.

[0053] The horizontal sliding module includes: horizontal slide rails 3 and 12, a horizontal sliding power system 9 and 11, a water tank guide rail base 8, and a limit sensor 2. Taking one side as an example, the horizontal slide rail 3 is composed of a horizontal slide rail 301, a horizontal lead screw 302, and a horizontal slide rail connecting plate 303. The fully sealed horizontal slide rail 3 can provide stable conduction, guide movement, and isolate external dust. Figure 3 As shown; Module 1 (3) and Module 2 (12) of the horizontal slide rails are symmetrically distributed on both sides of the water tank 20; the horizontal sliding power system 9 is driven by a servo motor 901, wherein the motor drive shaft is connected to the horizontal lead screw 302 through a rigid coupling 902; the horizontal slide rails 3 and 12 and the horizontal sliding power systems 9 and 11 are all fixed to the top of the water tank guide rail base 8 by the horizontal slide rail connecting plate 303; the limit sensor 2 is located at the end of the horizontal slide rails 3 and 12 to prevent the movement from exceeding the specified stroke, such as... Figure 3 As shown.

[0054] The active flow control module includes: sliders 4 and 16, a fixed bracket 6, a retractable rectifier net 18, and an active flow control assembly. The active flow control assembly connects the measured cylinder 18 to the output shaft of the flow control servo motor 7 via a rigid coupling 17. The motion of the flow control servo motor 7 can be transmitted to the measured cylinder 18, thereby achieving active control. Figure 4 As shown; the end of the cylinder being tested is suspended freely, and the distance between the bottom surface of the cylinder 18 and the bottom of the water tank 20 is less than 5cm, which is to reduce the tip effect of the cylinder 18; the sliders 4 and 16 on both sides are mounted on the horizontal slide rails 3 and 12, and the internal threads are matched with the horizontal lead screw 302. The horizontal sliders 4 and 16 can be controlled to move linearly along the horizontal slide rails 3 and 12; the sliders 4 and 16 on both sides are connected by a fixed bracket 6, which is perpendicular to the horizontal slide rails 3 and 12 at both ends; a retractable rectifier net 19 is installed on both sides of the fixed bracket 6. The rectifier net 19 can clean up the eddies generated in the previous experiment during the return trip of the experiment, so as to break up the eddies left over from the previous experiment.

[0055] The state detection module includes a speed sensor 15, a vibration collector 5, a motion controller 503, a feedback unit 501, and a display screen 502. The input of the feedback unit 501 is connected to the speed sensor 15 and the vibration collector 5 of the active flow control module, and its output is connected to the display screen 502. The input of the motion controller 503 is connected to the feedback unit 501 to receive feedback signals from the system, and its output is connected to the first horizontal power assembly 9, the second horizontal power assembly 11, and the servo motor 7 of the active flow control module to execute commands given by the manipulator 504, such as... Figure 5 As shown.

[0056] This embodiment of a flow control experimental method with adjustable wall confinement effect includes the following steps:

[0057] The first step is to fill water tank 20 with water to a height of about 4 / 5 of the tank's height. This is to reduce the impact of the water surface on the test surface. Then, an appropriate amount of tracer particles are added.

[0058] The second step is to identify the key parameters of this experiment, such as the blocking ratio, Reynolds number, control law, etc., and input each parameter into the manipulator 504.

[0059] Thirdly, upon receiving the new blocking ratio requirement, the feedback unit 501 first drives the horizontal servo motor 10 to rotate, adjusting the spacing of the side plates 21 of the water tank. Then, the distance sensor 143 feeds back the current spacing, providing closed-loop feedback to the motion controller 503. Ultimately, the desired blocking ratio is achieved.

[0060] In the fourth step, the feedback unit 501 receives a new Reynolds number requirement. First, the motion controller 503 drives the first horizontal motion component 9 and the second horizontal motion component 11 to achieve stable movement. Subsequently, the speed sensor 15 and the vibration collector 5 feed back the current speed and vibration to the motion controller 503 to detect the current motion state.

[0061] The fifth step involves using particle image velocimetry to obtain the current flow state, which serves as the input to the motion controller 503. Specifically, as follows... Figure 6 As shown.

[0062] In the sixth step, the current flow state is used as input. The flow control servo motor 7 receives the signal from the motion controller 503 and can execute an effective control law to enhance turbulent mixing in the wake or to harvest energy based on vortex-induced vibration.

[0063] Step 7: Stretch the rectifier net 19 into the water tank. The motion controller 503 sends a return signal, which can also clean up the residual vortex in the water tank 20.

[0064] Step 8: Repeat steps 2 through 7 to explore a wider parameter space.

[0065] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention without departing from the principles and spirit of the present invention.

Claims

1. An experimental method for a flow control experimental system with adjustable wall confinement effect, characterized in that: The wall-constraint effect adjustable flow control experimental system includes a water tank module, an active flow control module for controlling the rotation of the test bluff body within the water tank module, a horizontal sliding module for controlling the movement of the test bluff body within the water tank module, and a state detection module for monitoring and controlling the experimental state. The water tank module includes a water tank body with adjustable wall confinement effect, two side plates located inside the water tank body, and a lateral movement mechanism that drives the side plates to move in opposite directions. The two side plates are parallel to each other and parallel to the water flow direction inside the water tank body. The lateral movement mechanism controls the side plates to move in opposite directions perpendicular to the water flow, thereby adjusting the distance between the two side plates. The adaptive adjustment of the blockage ratio is achieved by adjusting the distance between the two walls. The active flow control module includes a fixed bracket, a flow control servo motor, and a retractable rectifier net. The fixed bracket is mounted on the water tank base, on which the flow control servo motor is installed, and on both sides of the fixed bracket are retractable rectifier nets. The experimental method, specifically the following steps: Step 1: Pour water into the water tank body, controlling the water level at 4 / 5 of the height of the water tank body; then add an appropriate amount of tracer particles to the water tank; Step 2: Input the experimental parameters into the controller. The experimental parameters include the blocking ratio, Reynolds number, and control law. Step 3: Based on the blocking ratio requirement received by the feedback device, the motion controller controls the horizontal servo motor to work, so as to adjust the distance between the two side plates inside the water tank body; at the same time, the distance sensor feeds back the current distance between the two side plates, and the closed-loop feedback is sent to the motion controller to adaptively adjust the blocking ratio to achieve the expected blocking ratio. Step 4: Based on the Reynolds number requirement received by the feedback device, the motion controller controls the horizontal sliding module to move the tested blunt body stably between the two side plates; the current movement speed and vibration are fed back to the motion controller through the speed sensor and vibration acquisition device to detect the current motion state; Step 5: Obtain the current flow state using particle image velocimetry (PEV) technology; Step 6: Use the current flow state as the input to the motion controller, which controls the active flow control module to drive the measured blunt body to rotate and execute an effective control law to enhance turbulent mixing in the wake or to harvest energy based on vortex-induced vibration. Step 7: Stretch the retractable rectifier net into the water tank body, and the motion controller sends a return signal to clear the residual vortex in the water tank body; Step 8: Repeat steps 2 through 7 to explore a wider parameter space.

2. The experimental method according to claim 1, characterized in that: The water tank module also includes a frame-structured water tank base, in which the water tank body is embedded; the lateral movement mechanism is installed on the water tank base and includes a lateral lead screw and a lateral servo motor. The lateral lead screw passes through the reverse threaded holes on the two side plates in sequence. The lateral servo motor drives the lead screw to rotate, converting the rotational motion of the lateral lead screw into the linear motion of the two side plates along the lateral lead screw, so that the two side plates move away from each other or closer together.

3. The experimental method according to claim 2, characterized in that: The top of the side plate is provided with a hanging lug along the extension direction of the plate surface. The hanging lug has a threaded hole that mates with the transverse lead screw. The threaded holes of the two side plates have opposite thread directions.

4. The experimental method according to claim 3, characterized in that: The output end of the flow control servo motor is connected to the blunt body under test via a coupling, and the blunt body under test is suspended between the two side plates inside the water tank body.

5. The experimental method according to claim 4, characterized in that: The distance between the bottom surface of the tested blunt object and the bottom surface of the water tank body is less than 5cm.

6. The experimental method according to claim 5, characterized in that: The horizontal sliding module includes two identical sets of horizontal slide rails arranged symmetrically, which are respectively installed on opposite sides of the water tank base via the water tank guide rail base; the horizontal slide rail includes a horizontal lead screw and a slider, with two sliders respectively installed on both sides of the fixed bracket; the horizontal lead screw is driven to rotate by a horizontal power component, and the rotational motion of the horizontal lead screw is converted into the linear motion of the fixed bracket along the axis of the horizontal lead screw driven by the slider, thereby driving the blunt object being measured to move in the water tank.

7. The experimental method according to claim 6, characterized in that: The horizontal sliding module also includes a horizontal sliding rail, which is a closed structure and is installed on the water tank guide rail base through a horizontal sliding rail connecting plate. A horizontal lead screw is rotatably installed inside the rail to stabilize transmission, guide movement, and isolate external dust. A limit sensor is installed at the end of the horizontal sliding rail to prevent movement from exceeding the specified stroke.

8. The experimental method according to claim 7, characterized in that: The state detection module includes a velocity sensor, a vibration collector, a distance sensor, a motion controller, a feedback unit, and a display screen. The velocity sensor and vibration collector are mounted on the active flow control module, and the distance sensor is mounted on the inner wall of both side plates. The input end of the feedback unit is connected to the velocity sensor, vibration collector, and distance sensor to receive signals, and its output end is connected to the display screen and the motion controller, respectively. The motion controller receives the feedback signal and outputs commands to the active flow control module and the horizontal sliding module to achieve motion control of the measured blunt body; it also outputs commands to the water tank module to adjust the limiting effect of the two walls.

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