Intelligent Control System and Method for Cylindrical Gap Shape Based on Active Airbag Drive

Abstract

This invention discloses an intelligent control system and method for cylindrical gap shape based on active airbag drive. It includes a floating ring disposed around a rotating shaft, an outer cavity disposed around the floating ring, and a front and rear cover for the rotating shaft to pass through and sealed to both ends of the floating ring and the outer cavity. The inner surface of the floating ring and the outer surface of the rotating shaft form the main gap fluid flow channel. The inner surface of the outer cavity has circumferentially distributed airbag placement grooves, in which multiple independently controllable elastic airbags are placed and contact the outer surface of the floating ring. The elastic airbags can be controlled by an external air passage to control the local inflation volume of the elastic airbags, simultaneously pushing the floating ring to move and thus adjusting the gap shape. This invention simulates different cylindrical gaps formed by processing and assembly errors in actual engineering, and adjusts the local air film stiffness damping characteristics and floating ring position in a timely manner according to the different vibration amplitude and direction of the rotating shaft, achieving real-time and precise control of the gap state and system dynamic characteristics.

Description

Technical Field

[0001] This invention relates to the technical field of non-contact cylindrical fluid sealing and gas lubrication, specifically to an intelligent control system and method for cylindrical gap shape based on active airbag drive, which is mainly applied to shaft end and interstage sealing and gas lubrication bearings of large turbine machinery such as steam turbines and compressors. Background Technology

[0002] Non-contact cylindrical gap seals are widely used in the shaft ends and interstages of turbine machinery such as steam turbines and gas turbines due to their advantages of simple structure, convenient installation, and high reliability. Innovation and breakthroughs in energy-saving and efficiency-enhancing technologies for cylindrical gap seals are of great significance.

[0003] The seal is fixedly installed on the sealing cavity, and its inner surface is machined with several regularly arranged holes and grooves. A small radial clearance is typically designed between the inner surface of the seal and the outer surface of the rotor to compensate for installation deviations, radial runout, and bending deformation of the shaft. This small clearance also constitutes the main channel for media leakage; the leaking gas or liquid undergoes multiple throttling and expansion effects, thereby reducing the leakage amount. Traditional fixed-installation cylindrical gap seals, due to errors during blind installation, will have an eccentric gap between their inner surface and the rotor surface. This eccentric gap has a significant negative impact on the seal's leakage and dynamic characteristics.

[0004] Existing methods for testing the shape of cylindrical clearances are insufficient for accurate measurement and active control of eccentric clearances. How to precisely adjust and measure cylindrical clearances with different eccentric shapes in simulated laboratory tests to simulate the eccentric clearance shapes that may occur in actual engineering projects is crucial for studying the sealing performance of cylindrical clearances under different eccentric sealing clearances. Furthermore, in real-world conditions, the rotor trajectory of a turbine changes in real time with varying operating conditions, such as unit start-up and shutdown, critical transitions, and variable operating condition adjustments.

[0005] How to actively control the position of the cylindrical gap sealing liner to achieve real-time changes in the gap, and thus adapt to the eccentric whirl of the rotor at different times, is also an important direction for the future development of cylindrical gap seals. Summary of the Invention

[0006] To address the problem that existing non-contact cylindrical gap sealing eccentricity testing platforms cannot achieve precise adjustment and active control of eccentric gaps, this invention provides an intelligent cylindrical gap shape adjustment system based on active airbag drive.

[0007] The technical solution adopted in this invention is as follows:

[0008] An intelligent control system for cylindrical gap shape based on active airbag drive includes a floating ring disposed around a rotating shaft, an outer cavity disposed around the floating ring, a front cover and a rear cover for the rotating shaft to pass through and sealed to both ends of the floating ring and the outer cavity; the inner surface of the floating ring and the outer surface of the rotating shaft form a main gap fluid flow channel; the inner surface of the outer cavity is circumferentially distributed with airbag placement grooves, and multiple independently controllable elastic airbags are placed in the airbag placement grooves and in contact with the outer surface of the floating ring; the elastic airbags can be controlled by an external air passage to control the local inflation volume of the elastic airbags, while pushing the floating ring to move, thereby adjusting the gap shape;

[0009] It also includes an active control device, which includes a displacement sensor, an eddy current sensor, an electromagnetic proportional valve, a controller, and a PC host computer; the front end cover has vertically distributed eddy current sensor mounting holes on its side, and the eddy current sensor is fixed to the eddy current sensor mounting holes through the eddy current sensor mounting base to monitor the eddy current vortex of the rotating shaft; the outer cavity has circumferentially distributed displacement sensor mounting threaded holes, and the displacement sensor is installed on the outer cavity through the threaded holes to measure the displacement of the floating ring in real time;

[0010] Furthermore, the eddy current sensor measures the eddy current state of the rotating shaft, and the displacement sensor measures the circumferential position and displacement of the floating ring; the signals from the eddy current sensor and the displacement sensor are transmitted to the PC host computer, processed by the PC host computer's PID algorithm, and input to the downstream controller through the control panel to drive the airbag pressure inlet electromagnetic proportional valve, thereby realizing active control of the elastic airbag and the shape of the cylindrical gap.

[0011] Furthermore, an airbag mounting hole is provided in the outer cavity corresponding to the center position of the elastic airbag. The threaded part of the air nozzle of the elastic airbag passes through the airbag mounting hole in the outer cavity and is connected to the external air circuit through a connecting pneumatic connector.

[0012] Furthermore, an intelligent control system for cylindrical gap shape based on active airbag drive also includes a gap adjustment screw, which is connected to the gap adjustment screw mounting hole in the outer cavity to assist the movement of the floating ring.

[0013] Furthermore, the rear end cover and the front end cover are respectively provided with sealing ring mounting groove A and sealing ring mounting groove B. Low friction O-rings are respectively installed in sealing ring mounting groove A and sealing ring mounting groove B, and contact the end faces of the floating ring on both sides to prevent fluid leakage in the gap when the floating ring moves up and down.

[0014] Furthermore, air-leakage sealing rings are respectively provided at the contact positions between the rear end cover, the front end cover and the outer cavity.

[0015] Furthermore, the system includes four elastic airbags, four displacement sensors, and two eddy current sensors. The four elastic airbags, four displacement sensors, and two eddy current sensors are arranged at a 90° angle to each other to achieve measurement of the eccentricity of the floating ring and the dynamic condition of the rotating shaft in the Cartesian coordinate system.

[0016] Furthermore, the elastic airbag is tile-shaped, with an air nozzle on its outer arc-shaped surface. When air is inflated into the elastic airbag, its inner and outer arc-shaped surfaces will deform (bulge).

[0017] Furthermore, an intelligent control system for cylindrical gap shape based on active airbag drive includes multiple elastic airbags, displacement sensors, and gap adjustment screws arranged along the axis of rotation, thereby constructing an axially eccentric non-uniform gap working condition with differences in the system's inlet and outlet.

[0018] A control method for a cylindrical gap shape intelligent control system based on active airbag drive includes the following steps:

[0019] Manual quick adjustment process:

[0020] In the initial state, the concentricity, eccentricity and three-dimensional tilt of the floating ring can be quickly adjusted by adjusting the gap screw, so as to realize the rapid simulation of the initial state under different gap working conditions;

[0021] Automatic intelligent adjustment process:

[0022] Step 1) In the initial state, the elastic air bladders around the floating ring are filled with gas at a predetermined pressure;

[0023] Step 2) When the floating ring has an eccentric gap relative to the rotating shaft, the displacement sensor obtains the relative position information of the floating ring, and the eddy current sensor obtains the axis position information of the rotating shaft. The displacement sensor and the eddy current sensor transmit voltage signals to the PC host computer respectively. After dynamic adjustment by PID algorithm, the PC host computer adjusts the pressure of the elastic airbag and feeds back the position of the floating ring through the displacement sensor. The eccentric state of the floating ring at each moment is adjusted in real time to adjust the shape of the air film gap and correct the eccentricity of the floating ring.

[0024] Step 3) When the floating ring tilts in three dimensions relative to the rotating shaft, the displacement sensor acquires the relative position information of the front and rear ends of the floating ring, and the eddy current sensor acquires the position information of the shaft center. The displacement sensor and the eddy current sensor transmit voltage signals to the PC host computer, which performs dynamic adjustment through PID algorithm. The PC host computer adjusts the pressure of the elastic airbag and feeds back the position of the floating ring through the front and rear displacement sensors, thereby adjusting the tilt state of the floating ring at each moment in real time, so as to adjust the shape of the air film gap and correct the three-dimensional tilt of the floating ring.

[0025] Advantages and benefits of this invention:

[0026] 1) This invention introduces a circumferentially locally controllable active control structure, namely a flexible airbag and a corresponding control device, on the back of the floating ring. This enables convenient and precise adjustment of different gap shapes, including concentric annular, eccentric annular, or three-dimensional inclined gaps, to achieve a fixed stator-type cylindrical surface gap seal. This simulates the different sealing gaps formed by processing and assembly errors in actual engineering.

[0027] 2) The intelligent control system for cylindrical gap is more adaptive, and the active control structure for circumferential local control is relatively independent. It can adjust the local air film stiffness and damping characteristics and floating ring position of the system in a timely manner according to the different vibration amplitude and direction of the rotating shaft. Therefore, the dynamic characteristics and gap state control of the system are more precise.

[0028] 3) This invention simulates the different cylindrical gaps caused by processing and assembly errors in actual engineering, and adjusts the local air film stiffness damping characteristics and floating ring position of the system in a timely manner according to the different vibration amplitude and direction of the rotating shaft, so as to realize real-time and precise control of the gap state and system dynamic characteristics. Attached Figure Description

[0029] Figure 1 This is an axial cross-sectional view of the active airbag cylindrical gap adjustment system according to Embodiment 1 of the present invention;

[0030] Figure 2 This is a three-dimensional model diagram of the active airbag cylindrical gap adjustment system according to Embodiment 1 of the present invention;

[0031] Figure 3 This is a cross-sectional view AA of the outer cavity of the active airbag cylindrical gap adjustment system according to Embodiment 1 of the present invention;

[0032] Figure 4 This is a cross-sectional view of the mid-surface (BB) of the front cover of the active airbag cylindrical gap adjustment system according to Embodiment 1 of the present invention;

[0033] Figure 5 This is a three-dimensional model diagram of the floating ring of the present invention;

[0034] Figure 6 This is a three-dimensional model diagram of the elastic airbag of the present invention;

[0035] Figure 7 These are the three-dimensional model and axial cross-sectional view of the rear end cover of this invention;

[0036] Figure 8 These are the three-dimensional model diagram and axial cross-sectional diagram of the external cavity of this invention;

[0037] Figure 9 These are the three-dimensional model and axial cross-sectional view of the front cover of this invention;

[0038] Figure 10This is a circumferential cross-sectional view and a working principle diagram of the active airbag cylindrical gap adjustment system according to Embodiment 1 of the present invention;

[0039] Figure 11 This is a three-dimensional model diagram of the active airbag cylindrical gap adjustment system according to Embodiment 2 of the present invention;

[0040] Figure 12 This is an internal schematic diagram of the active airbag cylindrical gap adjustment system according to Embodiment 2 of the present invention;

[0041] Figure 13 This is a physical diagram of the elastic airbag installation of the present invention;

[0042] Figure 14 This is a photograph of the elastic airbag of the present invention;

[0043] Figure 15 This is a physical diagram of the system platform of the present invention.

[0044] Figure 16 This is a graph showing the experimental test results of the gap flow rate of the present invention;

[0045] Figure 17 This is a diagram showing the displacement relationship of the floating ring of the present invention as the airbag pressure changes;

[0046] In the diagram: 1. Rotating shaft; 2. Floating ring; 2-1. Inner surface of the floating ring; 2-2. End face of the floating ring; 2-3. Outer surface of the floating ring; 3. Elastic airbag; 3-2. Threaded part of the air nozzle; 4. Rear end cover; 4-1. Sealing ring mounting groove A; 5. Outer cavity; 5-1. Displacement sensor mounting threaded hole; 5-2. Airbag placement groove; 5-3. Airbag mounting hole; 5-4. Gap adjustment screw mounting hole; 6. Front end cover; 6-1. Mounting hole; 6-2. Eddy current sensor mounting hole; 7. Low friction O-ring; 8. Anti-air leakage sealing ring; 9. Displacement sensor; 10. Pneumatic connector; 11. Eddy current sensor mounting base; 12. Eddy current sensor; 13. Gap adjustment screw. Detailed Implementation

[0047] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0048] Example 1: Reference Figure 1-9 A cylindrical gap shape intelligent control system based on active airbag drive mainly includes a rotating shaft 1, a floating ring 2, an elastic airbag 3, a rear end cover 4, an outer cavity 5, a front end cover 6, a low-friction O-ring 7, an air leakage prevention sealing ring 8, a displacement sensor 9, a pneumatic connector 10, an eddy current sensor mounting base 11, an eddy current sensor 12, and a gap adjustment screw 13.

[0049] The inner surface 2-1 of the floating ring and the outer surface of the rotating shaft 1 form the main gap fluid flow channel. The inner surface of the outer cavity has circumferentially distributed airbag placement grooves 5-2. Multiple independently controllable elastic airbags 3 are placed in the airbag placement grooves 5-2 and contact the outer surface 2-3 of the floating ring. The outer cavity 5 has an airbag mounting hole 5-3 corresponding to the center position of the elastic airbag. The threaded part 3-2 of the airbag nozzle 3 passes through the airbag mounting hole 5-3 of the outer cavity 5 and is connected to an external air circuit via a pneumatic connector 10. The elastic airbag 3 can control the inflation amount of a local elastic airbag 3 through the external air circuit, simultaneously pushing the floating ring 2 to move, thereby adjusting the gap shape. The outer cavity 5 has several displacement sensor mounting threaded holes 5-1 distributed circumferentially. Displacement sensors 9 are mounted on the outer cavity 5 through the threaded holes 5-1 to measure the displacement of the floating ring 2 in real time. The gap adjusting screw 13 is connected to the gap adjusting screw mounting hole 5-4 of the outer cavity 5 to assist the movement of the floating ring 2. Two eddy current sensor mounting holes 6-2 are vertically distributed on the side of the front cover 6. The eddy current sensor 12 is fixed to the mounting hole 6-2 by the eddy current sensor mounting base 11 to monitor the eddy current vortex of the rotating shaft. The rear cover 4 and the front cover 6 are respectively provided with sealing ring mounting grooves A4-1 and B6-1. Low friction O-rings 7 are installed in sealing ring mounting grooves A4-1 and B6-1 and contact the floating ring end faces 2-2 on both sides of the floating ring 2 to prevent fluid leakage in the gap when the floating ring moves up and down.

[0050] Reference Figure 10 The active control device consists of a displacement sensor 9, an eddy current sensor 12, an electromagnetic proportional valve, a controller (lower-level controller), a PC host computer, an air supply source, a filter dryer, and a storage device. The eddy current sensor 12 can measure the eddy current state of the rotating shaft 1, and the displacement sensor 9 can accurately measure the circumferential position and displacement of the floating ring 2. The voltage signals of the eddy current sensor 12 and the displacement sensor 9 are transmitted to the PC host computer. A PID algorithm is written on the PC host computer and input to the downstream controller through the control panel to drive the electromagnetic proportional valve, so as to realize the active control of the elastic airbag 3 and the cylindrical gap shape, so as to achieve the purpose of adapting the cylindrical gap shape to the rotating shaft motion state.

[0051] Example 2: Refer to Figure 11-12 The difference between this and Embodiment 1 is the addition of a corresponding elastic airbag 3, displacement sensor 9, and gap adjustment screw 13 in the axial direction. This real-time example can construct an axially eccentric uneven gap condition with differences between the inlet and outlet of the active airbag cylindrical gap adjustment system, and use eight elastic airbags 3 to adjust and control the axially eccentric uneven gap in real time according to the actual working conditions.

[0052] Example 3: A method for intelligent control of cylindrical gap shape based on active airbag drive: including the following steps:

[0053] Manual quick adjustment process for the float ring:

[0054] The concentricity, eccentricity, and three-dimensional tilt of the floating ring can be quickly and conveniently adjusted by adjusting the gap screw, which facilitates rapid simulation of the initial state under different gap conditions.

[0055] Automatic intelligent adjustment process of the floating ring:

[0056] The air bladders around the floating ring are initially filled with gas at a predetermined pressure. This reduces the rigid impact on the floating ring during movement, enables faster and more precise control of the start and stop process of the control mechanism, and reduces the impact of the start and stop shock of the control mechanism.

[0057] In Embodiment 1, when the float ring has an eccentric gap relative to the shaft (taking the float ring being biased to the upper right as an example), the displacement sensor obtains the relative position information of the float ring, and the eddy current sensor obtains the position information of the shaft center. The displacement sensor and the eddy current sensor respectively transmit voltage signals to the PC host computer, and based on this, calculate the required increase in pressure ratio between the right airbag and the upper airbag, and push the float ring back to the concentric position with the shaft. This process additionally introduces a PID algorithm for dynamic adjustment, further reducing the impact of the working inertia and instability of the working mechanism on the basis of the inherent buffering characteristics of the airbag.

[0058] In Example 2, for the three-dimensional tilt state of the long floating ring structure (taking the front end as the upper part and the rear end as the lower part), the airbags around the front and rear ends are adjusted according to the gap control mechanism of Example 1, so that both ends are concentric with the rotating shaft, and finally the purpose of correcting the three-dimensional tilt is achieved.

[0059] Reference Figure 13 , 14 Figures 15 and 16 show actual images of the elastic airbag components, the elastic airbag installation, and the system platform construction of the present invention.

[0060] The advantages of using elastic airbags for active control in this invention are as follows:

[0061] 1) Uniformly distributed pressure (when the airbag inflates, its flexible surface naturally conforms to the surface of the object being pushed (even if it is irregularly shaped), distributing the thrust evenly across the entire contact surface. This greatly reduces local stress concentration and avoids damage to fragile, delicate, or surface-sensitive objects. It can also effectively push flexible or irregularly shaped objects).

[0062] 2) Excellent cushioning and shock absorption characteristics (the airbag material itself is elastic, and the inflation and deflation process itself has a certain degree of compressibility and damping effect. Smooth start / stop: The beginning and end of the pushing action are very gentle, avoiding rigid impact. Shock and vibration absorption: When encountering obstacles or external vibrations during the pushing process, the airbag can effectively absorb energy, protecting the pushed object and the pushing mechanism itself. Overload protection: If encountering excessive resistance, the airbag will compress and deform instead of forcibly pushing, playing a certain role in overload protection).

[0063] 3) Inherent safety and low risk (Using compressed air, even in the event of a rupture or leak, the risk of instantaneous energy release is far lower than that of a high-pressure hydraulic system. There is no danger of high-pressure liquid jetting).

[0064] 4) It can achieve complex movements (by combining and arranging multiple airbags and independently controlling the air pressure, more complex movements can be achieved, such as tilting, bending or wave-like propulsion).

[0065] 5) Adaptability and flexible contact (the airbag can automatically adapt to the contour and position changes of the object being pushed, without the need for high-precision positioning or complex guiding mechanisms; it simplifies system design, improves tolerance to workpiece tolerances and positioning errors, and is particularly suitable for handling objects with slight positional deviations in automated production lines).

[0066] Reference Figure 16 The experimental results of leakage are shown in the figure. Part (a) shows the change of leakage at the inlet and outlet over time; part (b) shows the change of leakage with the eccentricity of the floating ring. It can be seen that the leakage varies with different eccentricities. This can be used to guide the optimization design of the device, measure the reliability of the sealing structure under different working conditions, and demonstrate the superiority of the active elastic airbag control of this invention for gap shape adjustment.

[0067] Reference Figure 17 The graph showing the relationship between the float ring and the pressure change of the lower airbag demonstrates that the airbag-driven float ring exhibits stable controllability and excellent anti-interference capabilities.

[0068] The embodiments described in this specification are merely examples of implementations of the inventive concept. The scope of protection of this invention should not be considered as limited to the specific forms stated in the embodiments. The scope of protection of this invention also includes equivalent technical means that can be conceived by those skilled in the art based on the inventive concept.

Claims

1. A cylindrical gap shape intelligent control system based on active airbag drive, characterized in that, The system includes a floating ring (2) disposed around the rotating shaft (1), an outer cavity (5) disposed around the floating ring (2), a front end cap (6) and a rear end cap (4) through which the rotating shaft passes and which are sealed to both ends of the floating ring (2) and the outer cavity (5); the inner surface (2-1) of the floating ring (2) and the outer surface of the rotating shaft (1) form the main gap fluid flow channel; the inner surface of the outer cavity (5) is circumferentially distributed with airbag placement grooves (5-2), and multiple independently controllable elastic airbags (3) are placed in the airbag placement grooves (5-2) and in contact with the outer surface (2-3) of the floating ring; the elastic airbags (3) can be controlled by an external air passage to control the inflation of the elastic airbags (3), while pushing the floating ring (2) to move, thereby adjusting the gap shape; It also includes an active control device, which includes a displacement sensor (9), an eddy current sensor (12), an electromagnetic proportional valve, a controller, and a PC host computer; the front cover (6) has vertically distributed eddy current sensor mounting holes (6-2) on its side, and the eddy current sensor (12) is fixed on the eddy current sensor mounting hole (6-2) through the eddy current sensor mounting base (11) to monitor the eddy current vortex of the rotating shaft (1); the outer cavity (5) has circumferentially distributed displacement sensor mounting threaded holes (5-1), and the displacement sensor (9) is installed on the outer cavity (5) through the threaded hole (5-1) to measure the displacement of the floating ring (2) in real time; The eddy current sensor (12) measures the eddy current state of the rotating shaft (1), and the displacement sensor (9) measures the circumferential position and displacement of the floating ring (2). The signals from the eddy current sensor (12) and the displacement sensor (9) are transmitted to the PC host computer. The PC host computer processes the signals using a PID algorithm and inputs them to the downstream controller through the control panel to drive the electromagnetic proportional valve at the airbag pressure inlet, thereby achieving active control of the elastic airbag (3) and the shape of the cylindrical gap.

2. The intelligent control system for cylindrical gap shape based on active airbag drive according to claim 1, characterized in that, The outer cavity (5) has an airbag mounting hole (5-3) at the center of the elastic airbag. The threaded part (3-2) of the air nozzle of the elastic airbag (3) passes through the airbag mounting hole (5-3) of the outer cavity (5) and is connected to the external air circuit through the pneumatic connector (10).

3. The intelligent control system for cylindrical gap shape based on active airbag drive according to claim 1, characterized in that, It also includes a gap adjusting screw (13), which is connected to the gap adjusting screw mounting hole (5-4) of the outer cavity (5) to assist the movement of the floating ring (2).

4. The intelligent control system for cylindrical gap shape based on active airbag drive according to claim 1, characterized in that, The rear end cover (4) and the front end cover (6) are respectively provided with sealing ring mounting groove A (4-1) and sealing ring mounting groove B (6-1). Low friction O-rings (7) are respectively installed in sealing ring mounting groove A (4-1) and sealing ring mounting groove B (6-1) and contact the floating ring end faces (2-2) on both sides of the floating ring (2) to prevent fluid leakage in the gap when the floating ring moves up and down.

5. The intelligent control system for cylindrical gap shape based on active airbag drive according to claim 1, characterized in that, Air-leakage sealing rings (8) are respectively provided at the contact positions between the rear end cover (4), the front end cover (6) and the outer cavity (5).

6. The intelligent control system for cylindrical gap shape based on active airbag drive according to claim 1, characterized in that, The elastic airbags (3) are provided with 4 units, the displacement sensors (9) are provided with 4 units, and the eddy current sensors (12) are provided with 2 units. The 4 elastic airbags (3), 4 displacement sensors (9) and 2 eddy current sensors (12) are arranged at a 90° angle to each other to realize the measurement of the eccentric working condition of the floating ring (2) and the dynamic working condition of the rotating shaft (1) in the Cartesian coordinate system.

7. The intelligent control system for cylindrical gap shape based on active airbag drive according to claim 1, characterized in that, The elastic airbag (3) is tile-shaped, and its outer arc surface is provided with an air nozzle. When air is inflated into the elastic airbag (3), its inner and outer arc surfaces will deform.

8. The intelligent control system for cylindrical gap shape based on active airbag drive according to claim 3, characterized in that, It includes multiple elastic airbags (3) arranged axially along the rotating shaft (1), displacement sensors (9), and gap adjustment screws (13), thereby constructing an axially eccentric uneven gap condition with differences between the system inlet and outlet.

9. The control method of the intelligent control system for cylindrical gap shape based on active airbag drive according to any one of claims 1-8, characterized in that, Includes the following steps: Manual quick adjustment process: In the initial state, the concentricity, eccentricity and three-dimensional tilt of the floating ring can be quickly adjusted by adjusting the gap screw, so as to realize the rapid simulation of the initial state under different gap working conditions; Automatic intelligent adjustment process: Step 1) In the initial state, the elastic air bladders around the floating ring are filled with gas at a predetermined pressure; Step 2) When the floating ring has an eccentric gap relative to the rotating shaft, the displacement sensor obtains the relative position information of the floating ring, and the eddy current sensor obtains the axis position information of the rotating shaft. The displacement sensor and the eddy current sensor transmit voltage signals to the PC host computer respectively. After dynamic adjustment by PID algorithm, the PC host computer adjusts the pressure of the elastic airbag and feeds back the position of the floating ring through the displacement sensor. The eccentric state of the floating ring at each moment is adjusted in real time to adjust the shape of the air film gap and correct the eccentricity of the floating ring. Step 3) When the floating ring tilts in three dimensions relative to the rotating shaft, the displacement sensor acquires the relative position information of the front and rear ends of the floating ring, and the eddy current sensor acquires the position information of the shaft center. The displacement sensor and the eddy current sensor transmit voltage signals to the PC host computer, which performs dynamic adjustment through PID algorithm. The PC host computer adjusts the pressure of the elastic airbag and feeds back the position of the floating ring through the front and rear displacement sensors, thereby adjusting the tilt state of the floating ring at each moment in real time, so as to adjust the shape of the air film gap and correct the three-dimensional tilt of the floating ring.

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