A magnetic fluid seal reliability detection system based on optical detection technology

Abstract

The present invention provides a magnetic fluid seal reliability detection system based on optical detection technology, including a rotating wheel, a rotating spindle, a rotor, a sealing support component, gas, a left-stage shoe, a permanent magnet, a right-stage shoe, a first-stage light source generator bracket, a first-stage light source, a first-stage magnetic fluid, a first-stage video capture unit, a second-stage light source, a signal cable, a component bracket, a comprehensive analyzer, light, magnetic field lines of force, a pressure sensor, a second-stage magnetic fluid, a second-stage video capture unit, a light source generator, a flow channel, a rotor cavity, a sealing cavity, and a second-stage light source generator bracket. The first-stage magnetic fluid is heated by the first-stage light source, and information is transmitted to the first-stage video capture unit using the magnetic fluid Marangoni effect. The first-stage video capture unit transmits a signal to the comprehensive analyzer. Through the process of light-magnetic fluid-heat-magnetic fluid movement intensification-prediction of whether the device is leaking, the performance and status of the magnetic fluid sealing device can be predicted in advance, and accurate detection of the sealing device reliability can be achieved.

Description

Technical Field

[0001] The present invention relates to the field of optical detection technology, and in particular to a magnetic fluid seal reliability detection system based on optical detection technology. Background Art

[0002] Light has a certain degree of penetration and refraction effect on nano-magnetic fluids, and magnetic fluids are effective in sealing equipment in the industrial sector. They are widely used in the petrochemical, nuclear, bio-food and military fields. However, standards and industry specifications for magnetic fluid sealing technology are very rare. Since fluid (magnetic fluid) is used to seal fluid (medium), the reliability testing of magnetic fluid seals is difficult. Currently, there is no very reliable device or system for testing magnetic fluid seals. This poses a major safety hazard to the reliable operation of equipment and may even cause serious accidents under extreme working conditions, hindering the application and development of magnetic fluid seals. Summary of the Invention

[0003] To address the above issues, the present invention proposes a magnetic fluid seal reliability detection system based on optical detection technology. Through step-by-step detection and early warning, it can accurately predict the performance and status of the sealing device, thereby ensuring safety in the production process.

[0004] A magnetic fluid seal reliability detection system based on optical detection technology, the system comprising: a runner, a rotating spindle, a rotor, a seal support component, gas, a left-stage shoe, a permanent magnet, a right-stage shoe, a first-stage light source generator bracket, a first-stage light source, a first-stage magnetic fluid, a first-stage video capture unit, a second-stage light source, a signal cable, a component bracket, a comprehensive analyzer, light, magnetic field lines, a pressure sensor, a second-stage magnetic fluid, a second-stage video capture unit, a light source generator, a flow channel, a rotor cavity, a seal cavity, and a second-stage light source generator bracket;

[0005] The runner is a multi-blade type, rigidly connected to the rotating main shaft, rigidly connected to the rotor, and the runner rotates at high speed under the impact of the horizontal flow of gas. The runner drives the rotating main shaft to rotate synchronously, and the rotating main shaft drives the rotor to rotate synchronously. The gas flows at high speed in the flow channel and directly impacts the runner. The rotor is wrapped by a sealing support component, and the space formed is a closed rotor cavity. The sealing support component is cylindrical. The left stage shoe, permanent magnet, and right stage shoe are assembled on the sealing support component. The left stage shoe and the right stage shoe are circular transmission magnetic fields, and the permanent magnet is a circular emission magnetic field. There is a gap between the left stage shoe and the right stage shoe, and the gap is filled with magnetic fluid, namely first-stage magnetic fluid and second-stage magnetic fluid. The magnetic fluid plays a sealing role, and the rotating main shaft, first-stage magnetic fluid, left stage shoe, permanent magnet, right stage shoe, and second-stage magnetic fluid form a closed sealed cavity.

[0006] Furthermore, the first-stage light source generator bracket and the first-stage light source are both between the sealing support component and the rotating main shaft, the first-stage video capture unit is in the sealed cavity, the second-stage light source and the second-stage light source generator bracket are in the sealed cavity, the second-stage video capture unit is in the rotor cavity, and the pressure sensor is arranged on the connecting component between the bracket of the first-stage video capture unit and the second-stage light source generator bracket to detect the pressure changes in the sealed cavity. The comprehensive analyzer is arranged in the central control room outside the flow channel, and the comprehensive analyzer is connected to the first-stage video capture unit and the second-stage video capture unit through a signal cable. The first-stage video capture unit and the second-stage light source are connected together through the component bracket and the right-stage boot, and the component bracket serves as a fixed connection.

[0007] Furthermore, the permanent magnet N stage generates a magnetic field, which forms a closed magnetic field through the left stage shoe, the first stage magnetic fluid, the rotating main shaft, the second stage magnetic fluid, the right stage shoe, and the permanent magnet S stage. Under the action of the magnetic field, the magnetic fluid forms a liquid O-ring in the gap between the rotating main shaft and the magnetic fluid sealing device, which plays a sealing role.

[0008] Furthermore, the video capture unit is a high-speed camera with high resolution, which can capture the length changes of the spikes on the magnetic fluid layer. The video capture unit first pre-processes the collected pictures, including grayscale and normalization, and then extracts the spike information from the pictures, including the characteristic length of the spikes. Then, the similarity or difference of the compared spike characteristic lengths is calculated according to the hash algorithm, and according to the set warning range, a warning signal is issued when the similarity or difference of the comparison is within the warning range.

[0009] Furthermore, the working principle of the system is as follows: the first-stage light source emits irradiation light, which passes through the first-stage magnetic fluid. When the first-stage magnetic fluid is reliably sealed, the first-stage light source cannot irradiate the outermost layer of the first-stage magnetic fluid. When the sealing layer in the magnetic fluid sealing device is subjected to the excitation impact of the gas, so as to break open the inner layer of the first-stage magnetic fluid and reach the first-stage critical state of breakthrough, the first-stage light source directly irradiates the outermost layer of the first-stage magnetic fluid and heats the magnetic fluid. At this time, this part of the magnetic fluid forms thermal magnetic convection due to the Marangoni effect. The first-stage video capture unit detects this phenomenon through video and feeds back the information to the comprehensive analyzer. The comprehensive analyzer issues an early warning to remind the production staff on duty that the first-stage magnetic fluid seal is very fragile and the gas is about to leak until the first The first-stage magnetic fluid is completely broken through, and the pressure sensor detects the pressure change in the sealed cavity and feeds back the signal to the comprehensive analyzer. The comprehensive analyzer issues an early warning to remind the production staff on duty that the first-stage magnetic fluid seal has leaked; when the sealing layer is further stimulated and impacted by the gas, so that the inner layer of the second-stage magnetic fluid is broken through, and the second-stage breakthrough critical state is reached, the second-stage light source directly irradiates the outermost layer of the second-stage magnetic fluid and heats the magnetic fluid. At this time, this part of the magnetic fluid forms thermal magnetic convection due to the Marangoni effect. The second-stage video capture unit detects this phenomenon through video and feeds back the information to the comprehensive analyzer. The comprehensive analyzer issues an early warning to remind the production staff on duty that the second-stage magnetic fluid seal is already very fragile and needs to be stopped urgently to start repairing the equipment.

[0010] Furthermore, the Marangoni effect refers to the phenomenon of mass transfer due to the presence of a surface tension gradient at the interface of two liquids with different surface tensions. The intensity of the phenomenon is expressed by the following formula:

[0011] ;

[0012] ;

[0013] in, is the shear stress, is the temperature, is the temperature change value, is the magnetic fluid concentration, is the characteristic length of the magnetic fluid, is the dynamic viscosity, For heat diffusion, is the Marragoni number. The larger the value, the stronger the Marragoni effect. The Marragoni number is proportional to the temperature gradient, that is, the larger the temperature gradient, the stronger the Marragoni effect. When the laser acts on the magnetic fluid, the temperature of the magnetic fluid in the laser-irradiated part increases. Different from the surface tension of other magnetic fluids with lower temperatures, the surface tension difference drives the magnetic fluid, causing the liquid to move toward the boundary, which is manifested as the magnetic fluid spike generated by the Rosensweig effect being stretched under the increased surface tension, and the spike length increases.

[0014] The present invention proposes a magnetic fluid seal reliability detection system based on optical detection technology. When the sealing layer in the magnetic fluid seal device is subjected to the excitation impact of gas and reaches the point of breaking through the inner layer of the magnetic fluid, a light source can directly illuminate the outermost layer of the magnetic fluid and heat the magnetic fluid. At this time, this part of the magnetic fluid forms obvious thermal magnetic convection due to the Marangoni effect. A video capture unit detects this phenomenon through video and feeds the information back to a comprehensive analyzer, which then issues an early warning to remind production personnel on duty that the magnetic fluid seal is very fragile and gas is about to leak. At the same time, a first-level early warning is generated when the first-level magnetic fluid is about to leak. After the first-level magnetic fluid leaks, the pressure sensor again feeds back pressure change information, generating a second-level early warning to remind the device that a local leak has begun. When the second-level magnetic fluid is about to leak, feedback is again fed back, at this time an accident warning. In this way, the sealing leakage process of the magnetic fluid seal device is gradually layered, decomposed, and detected, and graded early warnings are issued. The physical change process of the magnetic fluid seal device is more accurately grasped and linked to the production safety process, thereby achieving accurate detection of the reliability of the magnetic fluid seal device and providing safety services for production. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0016] Figure 1 Schematic diagram of the overall structure of a magnetic fluid seal reliability detection system based on optical detection technology provided by an embodiment of the present invention;

[0017] Figure 2 This is a structural schematic diagram of a photoelectric detection magnetic fluid seal section of a magnetic fluid seal reliability detection system based on optical detection technology provided by an embodiment of the present invention;

[0018] Figure 3 Schematic diagram of the light source arrangement according to an embodiment of the present invention;

[0019] Figure 4 This is a schematic diagram of the working principle of a magnetic fluid seal reliability detection system based on optical detection technology provided by an embodiment of the present invention;

[0020] Figure 5 This is a graph showing the changing trend of the magnetic fluid peak length as the number of seal rupture layers increases under a high-resolution camera according to an embodiment of the present invention, where (a) shows the case where the seal layer is not ruptured, (b) shows the case where two seal layers are ruptured, and (c) shows the case where only one seal layer remains.

[0021] Figure 6 2 is a schematic diagram of the image comparison principle of the video capture unit provided by an embodiment of the present invention;

[0022] Figure 7 Schematic diagram of the installation position of the magnetic fluid seal reliability detection system provided by an embodiment of the present invention.

[0023] Explanation of the reference numerals: 1-wheel, 2-rotating spindle, 3-rotor, 4-sealing support component, 5-gas, 6-left-stage shoe, 7-permanent magnet, 8-right-stage shoe, 9-first-stage light source generator bracket, 10-first-stage light source, 11-first-stage magnetic fluid, 12-first-stage video capture unit, 13-second-stage light source, 14-signal cable, 15-component bracket, 16-integrated analyzer, 17-light, 18-magnetic field lines, 19-pressure sensor, 20-second-stage magnetic fluid, 21-second-stage video capture unit, 22-light source generator, 23-flow channel, 24-rotor cavity, 25-sealing cavity, 26-second-stage light source generator bracket. DETAILED DESCRIPTION

[0024] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0025] The present invention proposes a magnetic fluid seal reliability detection system based on optical detection technology, such as Figure 1 and Figure 2As shown, the system includes: a runner 1, a rotating spindle 2, a rotor 3, a sealing support component 4, a gas 5, a left-stage shoe 6, a permanent magnet 7, a right-stage shoe 8, a first-stage light source generator bracket 9, a first-stage light source 10, a first-stage magnetic fluid 11, a first-stage video capture unit 12, a second-stage light source 13, a signal cable 14, a component bracket 15, a comprehensive analyzer 16, light 17, magnetic field lines 18, a pressure sensor 19, a second-stage magnetic fluid 20, a second-stage video capture unit 21, a light source generator 22, a flow channel 23, a rotor cavity 24, a sealing cavity 25, and a second-stage light source generator bracket 26. Figure 1 AA is the cross-section position, and B is the photoelectric detection magnetic fluid sealing section.

[0026] The runner 1 is of a multi-blade type and is rigidly connected to the rotating main shaft 2. The rotating main shaft 2 is rigidly connected to the rotor 3. The runner 1 rotates at high speed under the impact of the horizontal flow of the gas 5. The runner 1 drives the rotating main shaft 2 to rotate synchronously, and the rotating main shaft 2 drives the rotor 3 to rotate synchronously. The gas 5 flows at high speed in the flow channel 23 and directly impacts and contacts the runner 1. The rotor 3 is wrapped by the sealing support component 4, and the space formed thereby is a closed rotor cavity 24. The sealing support component 4 is cylindrical in shape, which prevents the gas 5 from leaking along the rotating main shaft 2 to the space where the rotor 3 is located. The function of the seal is to prevent the gas 5 from flowing into the space. The left stage shoe 6, permanent magnet 7, and right stage shoe 8 are assembled on the sealing support component 4. These are all stationary components. The rotating main shaft 2 is the moving component. The left stage shoe 6 and the right stage shoe 8 are circular transmission magnetic fields, and the permanent magnet 7 is a circular emission magnetic field. There is a gap between the left stage shoe 6 and the right stage shoe 8, and the gap is filled with magnetic fluid, namely the first-stage magnetic fluid 11 and the second-stage magnetic fluid 20. The magnetic fluid plays a sealing role, so that the rotating main shaft 2, the first-stage magnetic fluid 11, the left stage shoe 6, the permanent magnet 7, the right stage shoe 8, and the second-stage magnetic fluid 20 form a closed sealed cavity 25.

[0027] In order to balance the external pressure, the sealed cavity 25 is also filled with gas of a certain pressure. One reason is to obtain a leakage signal. If there is a gas leak, the cavity pressure will decrease, and then the signal will be transmitted to the user. In addition, if there is a gas leak, the shape of the second-stage magnetic fluid 20 will change. After the second-stage video capture unit 21 obtains the shape change signal, it will transmit the signal to the user. Secondly, after the sealed cavity 25 is filled with gas of a certain pressure, the pressure of the outside gas 5 will be balanced by the magnetic fluid, which can improve the sealing ability of the magnetic fluid.

[0028] like Figure 2As shown, the first-stage light source generator bracket 9 and the first-stage light source 10 are both between the sealing support component 4 and the rotating main shaft 2, the first-stage video capture unit 12 is in the sealed cavity 25, the second-stage light source 13 and the second-stage light source generator bracket 26 are in the sealed cavity 25, the second-stage video capture unit 21 is in the rotor cavity 24, and the pressure sensor 19 is arranged on the connecting component between the bracket of the first-stage video capture unit 12 and the second-stage light source generator bracket 26, for detecting the pressure change in the sealed cavity 25. When the pressure drops rapidly, it indicates that there is a leakage in the first-stage magnetic fluid 11. The comprehensive analyzer 16 is arranged in the central control room outside the flow channel 23. The comprehensive analyzer 16 is connected to the first-stage video capture unit 12 and the second-stage video capture unit 21 through a signal cable 14. The first-stage video capture unit 12 and the second-stage light source 13 are connected together through the component bracket 15 and the right-stage boot 8, and the component bracket 15 plays the role of a fixed connection.

[0029] The permanent magnet 7 (N stage) generates a magnetic field, which forms a closed magnetic field through the left stage shoe 6, the first stage magnetic fluid 11, the rotating main shaft 2, the second stage magnetic fluid 20, the right stage shoe 8, and the permanent magnet 7 (S stage). Under the action of the magnetic field, the magnetic fluid forms a liquid O-ring in the gap between the rotating main shaft 2 and the magnetic fluid sealing device, which plays a sealing role.

[0030] The video capture unit is a high-speed, high-resolution camera that can capture the changing lengths of spikes in the magnetic fluid layer. In preliminary experiments, the length of the spikes is measured when only one layer of magnetic fluid remains. This length is used as a benchmark for comparison with the actual length of the spikes during operation. When the spike length reaches a predetermined range, the system signals an impending magnetic fluid seal rupture, prompting the turbine to shut down immediately, thereby preventing seal failure.

[0031] Figure 3 This is a schematic diagram of the distribution of light sources from the AA cross-sectional perspective provided by an embodiment of the present invention. The first-stage light source generator brackets 9 are evenly distributed along the rotating main axis 2. There are four first-stage light source generator brackets 9, which are located in the middle of the sealed gap filled with magnetic fluid when viewed from the cross section.

[0032] The working principle of the magnetic fluid sealing reliability detection system based on optical detection technology is as follows: the first-level light source 10 emits irradiation light, which passes through the first-level magnetic fluid 11. When the sealing of the first-level magnetic fluid 11 is very reliable, the first-level light source 10 cannot irradiate the outermost layer of the first-level magnetic fluid 11. When the sealing layer in the magnetic fluid sealing device is subjected to the excitation impact of the gas 5, so that the inner layer of the first-level magnetic fluid 11 is broken, and the first-level breakthrough critical state is reached, the first-level light source 10 can directly irradiate the outermost layer of the first-level magnetic fluid 11 and heat the magnetic fluid. At this time, this part of the magnetic fluid forms obvious thermal magnetic convection due to the Marangoni effect. At this time, the first-level video capture unit 12 detects the phenomenon through video and feeds back the information to the comprehensive analyzer 16. The comprehensive analyzer 16 reminds the production staff on duty that the first-level magnetic fluid seal is very fragile and the gas is about to leak. This is the first-level warning until the first-level magnetic fluid 11 is completely In the event of a complete leakage, the pressure sensor 19 detects a change in the pressure in the sealed cavity 25 and feeds back a signal to the comprehensive analyzer 16. The comprehensive analyzer 16 issues an early warning to remind the production staff on duty that the first-stage magnetic fluid seal has leaked and that they need to take immediate measures to prepare an emergency plan. This is a second-level early warning. When the sealing layer is further stimulated and impacted by the gas 5, so that the inner layer of the second-stage magnetic fluid 20 is broken open and the second-stage breakthrough critical state is reached, the second-stage light source 13 directly irradiates the outermost layer of the second-stage magnetic fluid 20 and heats the magnetic fluid. At this time, this part of the magnetic fluid forms obvious thermal magnetic convection due to the Marangoni effect. At this time, the second-stage video capture unit 21 detects the phenomenon through video and feeds back the information to the comprehensive analyzer 16. The comprehensive analyzer 16 issues an early warning to remind the production staff on duty that the second-stage magnetic fluid seal is already very fragile and needs to be stopped urgently to start repairing the equipment. This is an accident early warning.

[0033] The Marangoni effect refers to the phenomenon of mass transfer due to the presence of a surface tension gradient at the interface of two liquids (or a mixture of liquids, such as magnetic fluid) with different surface tensions. The intensity of the phenomenon is expressed by the following formula:

[0034] ;

[0035] ;

[0036] in, is the shear stress, is the temperature, is the temperature change value, is the magnetic fluid concentration, is the characteristic length of the magnetic fluid, is the dynamic viscosity, For heat diffusion, is the Marragoni number; a larger value indicates a stronger Marragoni effect. The above formula shows that shear stress is proportional to the temperature gradient; a larger temperature gradient indicates a stronger shear stress. In the present invention, as the magnetic fluid seal gradually fails, the magnetic fluid layer gradually becomes thinner, and the temperature gradient within it correspondingly increases, causing the Marragoni effect to gradually strengthen. When laser light irradiates the magnetic fluid seal layer, the irradiated area receives heat, causing a temperature change and generating a temperature gradient. The above formula shows that the Marragoni number is proportional to the temperature gradient; that is, a larger temperature gradient indicates a stronger Marragoni effect.

[0037] The Marangoni effect can be generated and enhanced by lasers and magnetic fields perpendicular to the surface of the magnetic fluid. When the laser acts on the magnetic fluid, the temperature of the laser-irradiated part of the magnetic fluid is higher, and the surface tension is different from that of other magnetic fluids with lower temperatures. Therefore, the surface tension difference drives the magnetic fluid, making it easier for the liquid to move toward the boundary. This is manifested as the magnetic fluid spikes generated by the Rosensweig effect being stretched under the increased surface tension, and the spike length increases.

[0038] like Figure 4 As shown, the present invention arranges the position of the first-level light source at the weakest place of the magnetic field, that is, the outermost layer of the magnetic fluid layer. Under normal conditions, the magnetic particles in the nanomagnetic fluid form chain lines according to the trend of the magnetic field lines 18, and then form chain surfaces, which act as a sealing barrier. The sealing is most unreliable at the weakest place of the magnetic field. Only at this point can the light 17 penetrate, allowing the first-level light source to heat the magnetic fluid. At the same time, this point is also the place where the sealing medium fluctuates the most. The weakest and most prone to failure points in the magnetic fluid sealing device can be captured, so that the location and time of failure of the sealing device can be accurately predicted.

[0039] When the sealed magnetic fluid layer begins to rupture, such as Figure 5 As shown in (b), the thickness of the magnetic fluid sealing section becomes smaller, and the temperature is relatively Figure 5 (a) When the magnetic fluid sealing layer has not yet broken, it rises slightly, which makes the Marangoni effect in the local area irradiated by the laser stronger and the peak longer; when only the last layer of the sealing layer is left, Figure 5 As shown in (c), the Marangoni effect is the strongest, the surface tension is also the largest, and the peak of the magnetic fluid layer is the longest.

[0040] The present invention transmits information to a first-stage video capture unit by emitting light through a first-stage light source, heating the first-stage magnetic fluid, and utilizing the Marangoni effect of the magnetic fluid. The first-stage video capture unit receives the signal and converts the optical signal into an electrical signal, and then transmits the signal to a comprehensive analyzer. Through the process of light-magnetic fluid-heat-magnetic fluid movement intensification-prediction device leakage, the reliability of the magnetic fluid sealing device can be predicted in advance.

[0041] Figure 6 This is a schematic diagram of the image comparison principle of the video capture unit. The principles of the first-level video capture unit and the second-level video capture unit are the same. The video capture unit first preprocesses the image, including grayscale and normalization to reduce irrelevant interference. It then extracts peak information from the image, mainly the characteristic length of the peak. Then, it calculates the similarity or difference of the compared peak characteristic lengths based on the hash algorithm. Finally, it sets a warning range. When the similarity or difference of the comparison is within the warning range, a warning signal will be given.

[0042] Figure 7 This is a schematic diagram of the installation position of the magnetic fluid seal reliability detection system proposed in the present invention. The outer diameter of the magnetic fluid seal of medium and large devices exceeds 50mm, and the larger one exceeds 1.9m. The sealing device of the present invention is a small device. As shown in the figure, the rotating spindle 2 is 10mm away from the inner wall of the shell, the distance between the rotating spindle 2 and the sealing support component 4 is 10mm, the distance between the center of the rotating spindle 2 and the sealing support component 4 is 20mm, and the distance between the rotating spindle 2 and the permanent magnet is greater than 20mm. The first-stage light source generator bracket 9 is an emitting head for installing a light source. The size of the first-stage light source generator bracket 9 is 5mm﹡4mm﹡3mm. The size of the transmitter head is smaller than that of the bracket. The light source generator 22 is outside the sealing device. The length, width and height of the first-level video capture unit 12 and the second-level video capture unit 21 are 6mm, 4mm and 6mm respectively. The first-level video capture unit 12 has a light. The thickness of the first-level light source 10 and the second-level light source 13 is less than 3mm, and the installation position of the first-level light source 10 and the second-level light source 13 is tilted at 30° in order to fully illuminate the first-level magnetic fluid 11 and the second-level magnetic fluid 20; the transmitter head of the first-level light source generator bracket 9 and the first-level video capture unit 12 are arranged at a 45° tilt in order to fit a smaller sealing gap.

[0043] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A magnetic fluid seal reliability detection system based on optical detection technology, characterized in that: The system includes: a runner, a rotating spindle, a rotor, a sealing support component, a gas, a left-stage shoe, a permanent magnet, a right-stage shoe, a first-stage light source generator bracket, a first-stage light source, a first-stage magnetic fluid, a first-stage video capture unit, a second-stage light source, a signal cable, a component bracket, a comprehensive analyzer, light, magnetic field lines, a pressure sensor, a second-stage magnetic fluid, a second-stage video capture unit, a light source generator, a flow channel, a rotor cavity, a sealing cavity, and a second-stage light source generator bracket; The runner is of multi-blade type, and is rigidly connected to the rotating main shaft, and the rotating main shaft is rigidly connected to the rotor. The runner rotates at high speed under the impact of the horizontal flow of gas, and the runner drives the rotating main shaft to rotate synchronously, and the rotating main shaft drives the rotor to rotate synchronously. The gas flows at high speed in the flow channel and directly impacts the runner. The rotor is wrapped by the sealing support component, and the space formed by it is a closed rotor cavity. The sealing support component is cylindrical. The left stage shoe, the permanent magnet, and the right stage shoe are assembled on the sealing support component. The left stage shoe and the right stage shoe are circular transmission magnetic fields, and the permanent magnet is a circular emission magnetic field. There is a gap between the left stage shoe and the right stage shoe, and the gap is filled with magnetic fluid, namely the first-stage magnetic fluid and the second-stage magnetic fluid. The magnetic fluid plays a sealing role, and the rotating main shaft, the first-stage magnetic fluid, the left stage shoe, the permanent magnet, the right stage shoe, and the second-stage magnetic fluid form a closed sealed cavity; The first-stage light source generator bracket and the first-stage light source are both between the sealing support component and the rotating main shaft, the first-stage video capture unit is in the sealed cavity, the second-stage light source and the second-stage light source generator bracket are in the sealed cavity, the second-stage video capture unit is in the rotor cavity, and the pressure sensor is arranged on the connecting part between the bracket of the first-stage video capture unit and the bracket of the second-stage light source generator, which is used to detect the pressure changes in the sealed cavity. The comprehensive analyzer is arranged in the central control room outside the flow channel, and the comprehensive analyzer is connected to the first-stage video capture unit and the second-stage video capture unit through a signal cable. The first-stage video capture unit and the second-stage light source are connected together through the component bracket and the right-stage boot, and the component bracket serves as a fixed connection.

2. The system according to claim 1, wherein: The permanent magnet N-stage generates a magnetic field, which forms a closed magnetic field through the left-stage shoe, the first-stage magnetic fluid, the rotating main shaft, the second-stage magnetic fluid, the right-stage shoe, and the permanent magnet S-stage. Under the action of the magnetic field, the magnetic fluid forms a liquid O-ring in the gap between the rotating main shaft and the magnetic fluid sealing device, which plays a sealing role.

3. The system according to claim 1, wherein: The video capture unit is a high-speed camera with high resolution that can capture the length changes of spikes on the magnetic fluid layer. The video capture unit first pre-processes the collected images, including grayscale and normalization, and then extracts spike information from the images, including the characteristic length of the spikes. Then, the similarity or difference of the characteristic lengths of the spikes is calculated based on the hash algorithm, and according to the set warning range, a warning signal is issued when the similarity or difference of the comparison is within the warning range.

4. The system according to claim 1, wherein: The working principle of the system is as follows: the first-stage light source emits irradiation light, which passes through the first-stage magnetic fluid. When the first-stage magnetic fluid is reliably sealed, the first-stage light source cannot irradiate the outermost layer of the first-stage magnetic fluid. When the sealing layer in the magnetic fluid sealing device is subjected to the excitation impact of the gas, so that the inner layer of the first-stage magnetic fluid is broken open and the first-stage critical state is reached, the first-stage light source directly irradiates the outermost layer of the first-stage magnetic fluid and heats the magnetic fluid. At this time, this part of the magnetic fluid forms a thermal magnetic convection phenomenon due to the Marangoni effect. The first-stage video capture unit detects this phenomenon through video and feeds back the information to the comprehensive analyzer. The comprehensive analyzer issues an early warning to remind the production staff on duty that the first-stage magnetic fluid seal is very fragile and the gas is about to leak until the first-stage magnetic fluid is released. The fluid is completely broken through, and the pressure sensor detects the change in pressure in the sealed cavity and feeds back the signal to the comprehensive analyzer. The comprehensive analyzer issues an early warning to remind the production staff on duty that the first-stage magnetic fluid seal has leaked; when the sealing layer is further stimulated and impacted by the gas, the inner layer of the second-stage magnetic fluid is broken open, and the second-stage breakthrough critical state is reached. The second-stage light source directly irradiates the outermost layer of the second-stage magnetic fluid and heats the magnetic fluid. At this time, this part of the magnetic fluid forms a thermal magnetic convection phenomenon due to the Marangoni effect. The second-stage video capture unit detects this phenomenon through video and feeds back the information to the comprehensive analyzer. The comprehensive analyzer issues an early warning to remind the production staff on duty that the second-stage magnetic fluid seal is already very fragile and needs to be stopped urgently to start repairing the equipment.

5. The system according to claim 4, characterized in that The Marangoni effect refers to the phenomenon of mass transfer due to the presence of a surface tension gradient at the interface of two liquids with different surface tensions. The intensity of the phenomenon is expressed by the following formula: Wherein, σ is shear stress, T is temperature, ΔT is temperature change, c is magnetic fluid concentration, L is characteristic length of magnetic fluid, η is dynamic viscosity, α is thermal diffusion, and Ma is Marraghni number. A larger value indicates a stronger Marraghni effect. The Marraghni number is proportional to the temperature gradient, i.e., a larger temperature gradient indicates a stronger Marraghni effect. When laser light acts on magnetic fluid, the temperature of the laser-irradiated portion of the magnetic fluid increases. Unlike the surface tension of other magnetic fluids with lower temperatures, the surface tension difference drives the magnetic fluid, causing the liquid to move toward the boundary. This is manifested as the magnetic fluid spike generated by the Rosensweig effect being stretched under the increased surface tension, and the spike length increases.

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