Measurement Device Based on Confined Vortex Structure Under Expanding Wall and Its Application

Abstract

This invention discloses a measurement device based on a confined vortex structure under an expanding wall and its application. The device includes a motor measurement and control device, a rectifier, an expanding wall confined vortex generator, and a frame structure placed inside a water tank. The frame structure is located on one side of the motor measurement and control device. The rectifier and the expanding wall confined vortex generator, located within the frame structure, are connected and fixed to the output end of the motor measurement and control device. This device addresses the shortcomings of existing technologies that neglect the influence of the expanding wall on vortex rings and whose vortex ring generator principles do not match practical applications. By applying this device, precise control of the velocity profile of the moving wall can be achieved, generating vortex rings with stable growth in different modes. It can also simultaneously measure and study the growth and evolution process of vortex structures, which is of great significance for the theoretical research of vortex rings. At the same time, it can provide experimental basis for the formulation of vortex structure parameters for cardiac function and cylinder design.

Description

Technical Field

[0001] This invention relates to the field of fluid mechanics experimental apparatus technology, specifically a measurement device based on a confined vortex structure under an expanding wall and its application. Background Technology

[0002] The study of confined vortex structures with expanding walls has significant theoretical and applied value for proposing new vortex ring parameters to reflect the heart function of vortex rings and optimizing fluid mixing and heat transfer efficiency in industrial processes, such as in the optimization of automobile cylinder design. One of the important factors influencing the morphology of vortex structures is the growth environment. Therefore, creating a vortex ring growth environment with controllable expanding walls and confined cavities is of great significance for both theoretical research and corresponding engineering practices.

[0003] Current experimental techniques only create limited environments, such as Figure 1 The image shows a confined vortex ring generator designed by Kelley C. Stewart in 2012, with a related research article published in the journal *Experiments in Fluids* titled "Vortex rings in radially confined domains." This device relies on a traditional piston to push fluid through a small pipe, causing the fluid boundary layer to swirl and form vortex rings at the pipe opening. These vortex rings then grow and evolve within a circumferentially confined large pipe. This experimental method differs somewhat from real-world engineering applications. The key difference lies in neglecting the influence of expanding moving walls. Similar to the formation of vortex rings in a heart or cylinder, vortex ring generation occurs through the expansion of the surrounding walls, causing fluid flow and ultimately forming vortex rings at the pipe opening. Figure 2 As shown, applying vortex-related theories, such as the formation number, to the diagnosis of ventricular function has not yielded ideal results. The formation number of ventricular vortices in patients is almost identical to that in normal individuals, indicating a significant difference between the vortices generated in the ventricle and those observed in existing experimental settings. Incomplete consideration of the experimental environment and insufficient understanding of the principles of vortex generation prevent existing traditional vortex theories from being applied in practice. Summary of the Invention

[0004] Purpose of the Invention: To address the shortcomings of existing technologies, this invention provides a measurement device based on a confined vortex structure under an expanding wall and its application. This device addresses the deficiencies of existing technologies, such as neglecting the influence of the expanding wall on vortex rings and the discrepancy between the principle of vortex ring generation devices and practical applications. By applying this device, precise control of the velocity profile of the moving wall can be achieved, generating vortex rings that grow stably in different modes. It can also simultaneously measure and study the growth and evolution process of vortex structures, which is of great significance for the theoretical research of vortex rings. At the same time, it can provide experimental basis for the formulation of vortex structure parameters for cardiac function and cylinder design.

[0005] Technical Solution: To achieve the above objectives, the present invention provides a measuring device based on an expanded wall confined vortex structure, comprising: a motor measuring and control device, a rectifier, an expanded wall confined vortex generator, and a frame structure placed inside a water tank. The frame structure is located on one side of the motor measuring and control device. The rectifier and the expanded wall confined vortex generator, located within the frame structure, are connected and fixedly connected to the output end of the motor measuring and control device. The rectifier and the expanded wall confined vortex generator are limited and fixed by multiple flanges vertically installed within the frame structure.

[0006] As a further preferred embodiment of the present invention, the motor measurement and control device includes a stepper motor controlled by a microcontroller, a drive screw and a piston rod, the output end of the stepper motor fixed on the base is fixedly connected to the lead screw, and a nut sleeved on the lead screw is fastened to one end of the piston rod;

[0007] When the stepper motor rotates forward or reverse, its output drives the lead screw to rotate in the forward or reverse direction. The nut fitted on the lead screw moves horizontally back and forth under the rotation of the lead screw, thereby driving the piston rod fixed to the nut to move horizontally back and forth as well. The relative motion between the nut and the lead screw here utilizes the lead screw and nut transmission principle. During operation, the nut is connected to the component that needs to perform linear reciprocating motion. The rotation of the lead screw drives the nut to perform linear reciprocating motion, thereby driving the component to perform linear reciprocating motion. Since this principle is existing technology, the attached diagram will not provide a detailed description of the structure.

[0008] As a further preferred embodiment of the present invention, the rectifier includes an inlet section, a rectifier section and a converging section connected in sequence by threads. The rectifier section is clamped on the flange used to fix and limit the rectifier to make the fluid entering the device flow uniformly. After the ambient fluid is drawn into the inlet section, it passes through the rectifier section composed of multiple rectifier meshes, flows through the converging section and then enters the expansion wall confined vortex generator.

[0009] As a further preferred embodiment of the present invention, the outlet end of the contraction section is smaller than the inlet end. By gradually reducing the cross-sectional area of ​​the channel, the fluid velocity is accelerated, the fluid kinetic energy is increased, the fluid becomes more uniform and stable, and turbulence is reduced. The contraction curve of the inner surface of the contraction section is as follows:

[0010]

[0011] Where x is the distance from the outlet to the inlet, and a 2 =3*L 2 R1 is the inlet size, R2 is the outlet size, and L is the length of the shrinkage curve.

[0012] As a further preferred embodiment of the present invention, the expanding wall confined vortex generating device includes an acrylic nozzle, a connector, a glass tube, and a particle inlet. The two ends of the connector are horizontally fixed to the acrylic nozzle and the glass tube, respectively. The other end of the acrylic nozzle is fixed to the contraction section, and the other end of the glass tube is fastened to the particle inlet. The piston rod passing through the glass tube and the particle inlet moves horizontally in a straight line under the power of a stepper motor.

[0013] The piston rod drives the piston at its end to move horizontally in the glass cylindrical tube. The volume inside the glass cylindrical tube increases or decreases, realizing the expansion and change of the wall surface, thereby simulating different expansion wall conditions in engineering practice. When the piston starts to move, the fluid flows in from the inlet section and forms a separation shear layer at the acrylic nozzle. The separation shear layer then rolls up in the glass tube to form a vortex ring.

[0014] As a further preferred embodiment of the present invention, by setting the distance between the piston and the nozzle orifice, and adjusting the diameter ratio of the acrylic nozzle and the glass tube, the growth and evolution environment of the vortex ring can be changed. This allows for the study of key parameters affecting the growth and evolution of the vortex ring, providing a more precise and controllable experimental environment for the study of confined vortex rings under expanding walls, and contributing to a deeper understanding of the vortex ring generation mechanism.

[0015] An application method for a measurement device based on a confined vortex structure under an expanding wall includes the following steps:

[0016] Step 1: Horizontally fix the rectifier and the confined vortex generator on the expanded wall inside the frame structure using an adjustable flange. Insert one end of the piston rod through the particle inlet and into the glass tube. Then place the entire frame structure into a water tank that matches its size to ensure that the frame can completely abut the inner edge of the water tank.

[0017] The other end of the piston rod is passed through the through hole on the side wall of the water cylinder and connected to the lead screw. The lead screw and the stepper motor are fastened together. A sealing ring is provided in the hole on the side wall of the water cylinder for placing the piston rod. The piston rod and the sealing ring on the side wall of the water cylinder are interference fit.

[0018] Step 2: Fill the water tank with water to ensure that the water level can submerge the entire device except for the frame. Use a microcontroller to control the stepper motor to drive the piston at the end of the piston rod to move to a distance of 5cm from the nozzle opening. This is the initial position.

[0019] Step 3: Spread hollow glass microspheres with a diameter of 60μm to 100μm in the water tank, and use a water pump connected to the inside of the water tank to circulate the hollow glass microspheres in the water. Turn on the laser located below the water tank, adjust the position of the light plane to ensure that it coincides with the center plane of the glass tube, and illuminate the entire flow field through the reflection of the hollow glass microspheres.

[0020] Step 4: Set the acceleration and deceleration time, movement distance, and maximum speed of the microcontroller program to meet the speed requirements. When studying the influence of the distance between the piston and the acrylic nozzle on the growth and evolution of the vortex ring, it is necessary to control variables, that is, to keep the speed consistent. While the stepper motor drives the piston rod to move, the synchronizer drives the high-speed camera to start shooting. The synchronizer controls the high-speed camera and the laser to work at the same time. The response time of the synchronizer is 10s to 12s.

[0021] Step 5: The high-speed camera captures the particle map of the entire flow field. The velocity field, vorticity field, circulation value, diameter and deformation of the confined vortex ring and the entire flow field under the expanding wall are calculated using the PIV post-processing software Fluere. Stability and oscillation uncertainty analysis are also performed.

[0022] Step Six: After completing the experiment, stop the stepper motor drive, reset the piston rod to the initial position, and repeat steps four and five to obtain the growth and evolution of the confined vortex rings generated by the expanding wall under different initial wall distances.

[0023] As a further preferred embodiment of the present invention, in step one, a mitral valve is installed in the acrylic nozzle of the confined vortex generator with an expanding wall. By adding a mitral valve, regurgitation phenomena can be studied, which provides a new experimental means for studying valvular heart disease.

[0024] As a further preferred embodiment of the present invention, in step two, a force sensor is provided between the piston rod and the lead screw. By setting the force sensor, the force on the glass tube, which serves as the wall, when the piston moves can be measured, that is, the force generated by ventricular dilation, providing a new experimental means for studying heart diseases.

[0025] As a further preferred embodiment of the present invention, in step four, the speed type is a ramp speed type, that is, the motion is divided into two parts: acceleration and deceleration. The acceleration time is 0.4s, the deceleration time is 0.6s, and the maximum speed is 1.0cm / s. This device is compatible with all speed type requirements, and the speed type can be adjusted according to the needs in the experiment.

[0026] Beneficial Effects: The measuring device based on a confined vortex structure under an expanded wall, and its application, as described in this invention, have the following advantages compared to existing technologies:

[0027] (1) This device solves the shortcomings of the experimental technique for studying the growth and evolution of vortex ring structures under expanded walls, and realizes the observation and analysis of confined vortex rings under expanded walls.

[0028] (2) By applying this device, the velocity of the moving wall can be precisely controlled, thereby generating vortex rings that grow stably in different modes;

[0029] (3) To provide experimental basis for the study of confined vortex structures under expanded walls, such as the formulation of vortex structure parameters for cardiac function and cylinder design;

[0030] (4) The consistent vortex ring growth and evolution parameters observed under the same experiment using this device demonstrate the stability and reliability of the experimental device and meet the requirements of experimental research. Attached Figure Description

[0031] Figure 1 This refers to a confined vortex ring generator in the prior art;

[0032] Figure 2 A schematic diagram illustrating the application of vortex theory to the diagnosis of ventricular function.

[0033] Figure 3 This is a schematic diagram of the structure of the present invention;

[0034] Figure 4 This is a schematic diagram of the internal structure of the contraction section;

[0035] Figure 5 A schematic diagram showing the connection between the motor measurement and control device, the rectifier, and the expanded wall confined vortex generator;

[0036] Figure 6 This is a schematic diagram of the framework structure;

[0037] Figure 7 This is a schematic diagram of the opening and closing state of the mitral valve;

[0038] Figure 8 This is a cross-sectional view simulating the heart. Detailed Implementation

[0039] The present invention will be further explained below with reference to the accompanying drawings and specific embodiments.

[0040] As shown in the attached figures, the measurement device based on the confined vortex structure under the expanding wall of the present invention includes: a motor measurement and control device consisting of a piston rod 9, a drive screw 10, and a stepper motor 11; a rectification device consisting of an inlet section 1, a rectification section 2, and a contraction section 4; an expanding wall confined vortex generating device consisting of an acrylic nozzle 5, a converter 6, a glass tube 7, and a particle inlet 8; and a frame structure for limiting and fixing the rectification device and the expanding wall confined vortex generating device.

[0041] The output end of the stepper motor 11, which is fixed on the base 110, is fixedly connected to the lead screw 10. The nut 101, which is sleeved on the lead screw 10, and one end of the piston rod 9 are fastened. When the stepper motor 11 rotates forward or backward, the output end of the stepper motor 11 drives the lead screw 10 to rotate in the forward or reverse direction. The nut 101, which is sleeved on the lead screw 10, moves horizontally forward and backward under the rotation of the lead screw 10, thereby driving the piston rod 9, which is fixed on the nut 101, to move horizontally forward and backward.

[0042] The other end of the piston rod 9 passes through the particle inlet 8 and extends into the glass tube 7. The piston rod 9 drives the piston at its end to move horizontally in the glass cylindrical tube 7, causing the volume inside the glass cylindrical tube 7 to increase or decrease, thereby realizing the wall expansion change and simulating different expansion wall conditions in engineering practice.

[0043] Example 1

[0044] Step 1: Horizontally fix the rectifier and the confined vortex generator on the expanded wall into the frame structure using an adjustable flange 12. Pass one end of the piston rod 9 through the particle inlet 8 and extend it into the glass tube 7. Then place the entire frame structure into the water tank 16 that is compatible with its size to ensure that the frame can completely abut the inner edge of the water tank 16.

[0045] After passing the other end of the piston rod 9 through the through hole on the side wall of the water cylinder 16, it is connected to the lead screw 10, and the lead screw 10 and the stepper motor 11 are fastened together.

[0046] Step 2: Fill the water tank 16 with water to ensure that the water level can submerge the entire device except for the frame. Use the microcontroller to control the stepper motor 11 to drive the piston at the end of the piston rod 9 to move to a distance of 5cm from the nozzle opening. This is the initial position.

[0047] Step 3: Hollow glass microspheres with a diameter of 60μm are seeded into water tank 16. These microspheres are circulated in the water by a water pump 13 connected inside water tank 16. After mixing with the water in water tank 16, the microspheres enter through inlet section 1, pass through rectifying section 2, contraction section 4, acrylic nozzle 5, and adapter 6, and then enter glass tube 7, where they abut against the piston. The laser 14 located below water tank 16 is activated, and the position of the light-emitting plane is adjusted to ensure it coincides with the center plane of glass tube 7. The reflection from the hollow glass microspheres illuminates the entire flow field.

[0048] Step 4: Set the microcontroller program's acceleration and deceleration time, movement distance, and maximum speed. The speed pattern is a ramp triangle, with an acceleration time of 0.4s, a deceleration time of 0.6s, and a maximum speed of 1.0cm / s. When studying the distance between the piston and the wall, the speed pattern needs to be kept consistent. While the stepper motor 11 drives the piston rod 9 to move, the synchronizer 15 drives the high-speed camera to start shooting. The synchronizer 15 simultaneously controls the high-speed camera and the laser 14 to work. The response time of the synchronizer 15 is 10s.

[0049] Step 5: The high-speed camera captures the particle map of the entire flow field. Through post-processing, the velocity field, vorticity field, circulation value, diameter and deformation of the confined vortex ring and the entire flow field under the expanding wall can be calculated, and stability and sway uncertainty analysis can be performed.

[0050] Step Six: After completing the experiment, stop the stepper motor 11 and reset the piston rod 9 to its initial position. Repeat steps four and five to obtain the growth and evolution of the confined vortex rings generated by the expanding wall under different initial wall distances.

[0051] Example 2

[0052] Step 1: Horizontally fix the rectifier and the confined vortex generator on the expanded wall into the frame structure using an adjustable flange 12. Pass one end of the piston rod 9 through the particle inlet 8 and extend it into the glass tube 7. Then place the entire frame structure into the water tank 16 that is compatible with its size to ensure that the frame can completely abut the inner edge of the water tank 16.

[0053] The other end of the piston rod 9 is passed through the through hole on the side wall of the water cylinder 16 and connected to one end of the force sensor 17. The other end of the force sensor is connected to the lead screw 10. The lead screw 10 and the stepper motor 11 are fastened together. The force sensor 17 is used to measure the force on the piston rod 9 when it moves in order to study the force generated by ventricular dilation.

[0054] Step 2: Fill the water tank 16 with water to ensure that the water level can submerge the entire device except for the frame. Use the microcontroller to control the stepper motor 11 to drive the piston at the end of the piston rod 9 to move to a distance of 5cm from the nozzle opening. This is the initial position.

[0055] Step 3: Hollow glass microspheres with a diameter of 80μm are seeded in water tank 16. A water pump 13 connected inside water tank 16 circulates the microspheres in the water. After mixing with the water in water tank 16, the microspheres enter through inlet section 1, pass through rectifying section 2, contraction section 4, acrylic nozzle 5, and adapter 6, and then enter glass tube 7, where they abut against the piston. The laser 14 located below water tank 16 is activated, and the position of the light-emitting plane is adjusted to ensure it coincides with the center plane of glass tube 7. The reflection from the hollow glass microspheres illuminates the entire flow field.

[0056] Step 4: Set the microcontroller program's acceleration and deceleration time, movement distance, and maximum speed. The acceleration time is 0.4s, the deceleration time is 0.6s, and the maximum speed is 1.0cm / s. This speed pattern is a ramp triangle. When studying the distance between the piston and the wall, the speed pattern needs to be kept consistent. While the stepper motor 11 drives the piston rod 9 to move, the synchronizer 15 drives the high-speed camera to start shooting. The synchronizer 15 simultaneously controls the high-speed camera and the laser 14 to work. The response time of the synchronizer 15 is 11s.

[0057] Step 5: The high-speed camera captures the particle map of the entire flow field. Through post-processing, the velocity field, vorticity field, circulation value, diameter and deformation of the confined vortex ring and the entire flow field under the expanding wall can be calculated, and stability and sway uncertainty analysis can be performed.

[0058] Step Six: After completing the experiment, stop the stepper motor 11 and reset the piston rod 9 to its initial position. Repeat steps four and five to obtain the growth and evolution of the confined vortex rings generated by the expanding wall under different initial wall distances.

[0059] Example 3

[0060] Step 1: Horizontally fix the rectifier and the confined vortex generator on the expansion wall inside the frame structure using an adjustable flange 12. Pass one end of the piston rod 9 through the particle inlet 8 and the glass tube 7 in sequence and then extend it into the acrylic tube 5 equipped with a mitral valve. Then place the entire frame structure into the water tank 16 that is compatible with its size to ensure that the frame can completely abut against the inner edge of the water tank 16.

[0061] The other end of the piston rod 9 is passed through a through hole in the side wall of the water cylinder 16 and connected to one end of the force sensor 17. The other end of the force sensor is connected to the lead screw 10. The lead screw 10 and the stepper motor 11 are fastened together. After the drive motor 11 is started, the piston rod 9 moves backward. When water flows towards the mitral valve device 18 made of plastic, the pressure of the fluid acts on the two valve discs of the mitral valve, pushing the valve discs to open. The fluid passes smoothly through the valve, which can simulate the growth and evolution of the vortex ring in the ventricle during the opening and closing of the mitral valve in a real heart. Figure 7 , Figure 8 As shown;

[0062] Step 2: Fill the water tank 16 with water to ensure that the water level can submerge the entire device except for the frame. Use the microcontroller to control the stepper motor 11 to drive the piston at the end of the piston rod 9 to move to a distance of 5cm from the nozzle opening. This is the initial position.

[0063] Step 3: Hollow glass microspheres with a diameter of 100μm are seeded in water tank 16. A water pump 13 connected inside water tank 16 circulates the microspheres in the water. After mixing with the water in water tank 16, the microspheres enter through inlet section 1, pass through rectifying section 2, contraction section 4, acrylic nozzle 5, and adapter 6, and then enter glass tube 7, where they abut against the piston. The laser 14 located below water tank 16 is activated, and the position of the light-emitting plane is adjusted to ensure it coincides with the center plane of glass tube 7. The reflection from the hollow glass microspheres illuminates the entire flow field.

[0064] Step 4: Set the microcontroller program's acceleration / deceleration time, movement distance, and maximum speed. The speed pattern is a ramp triangle, with an acceleration time of 0.4s, a deceleration time of 0.6s, and a maximum speed of 1.0cm / s. When studying the distance between the piston and the wall, the speed pattern needs to be kept consistent. While the stepper motor 11 drives the piston rod 9 to move, the synchronizer 15 drives the high-speed camera to start shooting. The synchronizer 15 simultaneously controls the high-speed camera and the laser 14. The response time of the synchronizer 15 is 12s.

[0065] Step 5: The high-speed camera captures the particle map of the entire flow field. Through post-processing, the velocity field, vorticity field, circulation value, diameter and deformation of the confined vortex ring and the entire flow field under the expanding wall can be calculated, and stability and sway uncertainty analysis can be performed.

[0066] Step Six: After completing the experiment, stop the stepper motor 11 and reset the piston rod 9 to its initial position. Repeat steps four and five to obtain the growth and evolution of the confined vortex rings generated by the expanding wall under different initial wall distances.

[0067] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A measuring device based on a confined vortex structure under an expanding wall, characterized in that: It includes: The motor measurement and control device, as well as the rectifier, the expansion wall confined vortex generator and the frame structure placed in the water tank (16), the frame structure is located on one side of the motor measurement and control device, the rectifier and the expansion wall confined vortex generator located in the frame structure are connected and fixed to the output end of the motor measurement and control device, the rectifier and the expansion wall confined vortex generator are limited and fixed by multiple flanges vertically installed in the frame structure. The expansion wall confined vortex generator includes an acrylic nozzle (5), an adapter (6), a glass tube (7), and a particle inlet (8). The two ends of the adapter (6) are horizontally fixed to the acrylic nozzle (5) and the glass tube (7), respectively. The other end of the acrylic nozzle (5) is fixed to the contraction section (4). The other end of the glass tube (7) is fastened to the particle inlet (8). The piston rod (9) passing through the glass tube (7) and the particle inlet (8) moves horizontally and linearly under the power of the stepper motor (11). The piston rod (9) drives the piston located at its end to move horizontally in the glass cylindrical tube (7). The volume inside the glass cylindrical tube (7) increases or decreases, realizing the expansion and change of the wall surface. When the piston starts to move, the fluid flows in from the inlet section (1) and forms a separation shear layer at the acrylic nozzle (5). The separation shear layer then rolls up in the glass tube (7) to form a vortex ring.

2. The measuring device based on a confined vortex structure under an expanding wall according to claim 1, characterized in that: The motor measurement and control device includes a stepper motor (11) controlled by a single-chip microcomputer, a drive screw (10) and a piston rod (9). The output end of the stepper motor (11) fixed on the base (110) is connected to the screw (10), and a nut (101) sleeved on the screw (10) and one end of the piston rod (9) are fastened together. When the stepper motor (11) rotates forward or reverse, the output end of the stepper motor (11) drives the lead screw (10) to rotate in the forward or reverse direction. The nut (101) sleeved on the lead screw (10) moves horizontally forward and backward under the rotation of the lead screw (10), thereby driving the piston rod (9) fixed on the nut (101) to move horizontally forward and backward.

3. The measuring device based on a confined vortex structure under an expanding wall according to claim 1, characterized in that: The rectifier includes an inlet section (1), a rectifier section (2), and a contraction section (4) connected in sequence by threads. The rectifier section (2) is clamped on the flange used to fix and limit the rectifier. After the ambient fluid is drawn into the inlet section (1), it passes through the rectifier section (2) which is composed of multiple rectifier nets (3), flows through the contraction section (4), and then enters the expansion wall confined vortex generator.

4. The measuring device based on a confined vortex structure under an expanding wall according to claim 3, characterized in that: The outlet end of the contraction section (4) is smaller than the inlet end, and the contraction curve of the inner surface of the contraction section (4) is as follows: Where x is the distance from the outlet to the inlet, and a 2 =3*L 2 R1 is the inlet size, R2 is the outlet size, and L is the length of the shrinkage curve.

5. A measuring device based on a confined vortex structure under an expanding wall, as described in claim 1, characterized in that: The distance between the piston and the nozzle (5) is set, and the diameter ratio of the acrylic nozzle (5) and the glass tube (7) is adjusted to change the vortex ring growth and evolution environment.

6. An application method for a measurement device based on a confined vortex structure under an expanding wall, characterized in that: It includes the following steps: Step 1: Fix the rectifier and the confined vortex generator on the expansion wall horizontally inside the frame structure using an adjustable flange (12). Insert one end of the piston rod (9) through the particle inlet (8) and into the glass tube (7). Then place the entire frame structure into a water tank (16) that is compatible with its size to ensure that the frame can completely abut against the inner edge of the water tank. After passing the other end of the piston rod (9) through the through hole on the side wall of the water cylinder (16), it is connected to the lead screw (10), and the lead screw (10) and the stepper motor (11) are fastened together; Step 2: Fill the water tank (16) with water to ensure that the water level can submerge the entire device except for the frame. Control the stepper motor (11) through the microcontroller to drive the piston at the end of the piston rod (9) to move to a distance of 5cm from the nozzle (5) opening. This is the initial position. Step 3: Spread hollow glass microspheres with a diameter of 60μm to 100μm in the water tank (16), and use the water pump (13) connected to the inside of the water tank to circulate the hollow glass microspheres in the water. Turn on the laser (14) located below the water tank, and adjust the position of the light plane to ensure that it coincides with the center plane of the glass tube (7). The entire flow field is illuminated by the reflection of the hollow glass microspheres. Step 4: Set the acceleration and deceleration time, movement distance and maximum speed of the microcontroller program to meet the speed requirements. When studying the influence of the distance between the piston and the acrylic nozzle (5) on the growth and evolution of the vortex ring, it is necessary to control variables, that is, keep the speed consistent. While the stepper motor (11) drives the piston rod (9) to move, the synchronizer (15) drives the high-speed camera to start shooting. The synchronizer (15) controls the high-speed camera and the laser (14) to work at the same time. The response time of the synchronizer (15) is 10s to 12s. Step 5: The high-speed camera captures the particle map of the entire flow field. The velocity field, vorticity field, circulation value, diameter and deformation of the confined vortex ring and the entire flow field under the expanding wall are calculated using the PIV post-processing software Fluere. Stability and oscillation uncertainty analysis are also performed. Step 6: After completing the experiment, stop the stepper motor (11) drive, reset the piston rod (9) to the initial position, and repeat steps 4 and 5 of the experiment to obtain the growth and evolution of the confined vortex ring generated by the expanding wall under different initial wall distances.

7. The application method of the measuring device based on the confined vortex structure under the expanding wall as described in claim 6, characterized in that: Step one: Install a mitral valve device (18) in the acrylic nozzle (5) of the expansion wall confined vortex generator.

8. The application method of the measuring device based on the confined vortex structure under the expanding wall as described in claim 6, characterized in that: In step two, a force sensor (17) is provided between the piston rod (9) and the lead screw (10).

9. The application method of the measuring device based on the confined vortex structure under the expanding wall as described in claim 6, characterized in that: In step four, the speed type is a ramp speed type, with an acceleration time of 0.4s, a deceleration time of 0.6s, and a maximum speed of 1.0cm / s.

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