Device for measuring performance of air floatation moving bearing surface type under-pressure static pressure thrust bearing and use method thereof

Abstract

The invention discloses an air floatation moving bearing surface type supercritical carbon dioxide static pressure thrust bearing pressure distribution measuring device, and belongs to the field of gas lubrication and performance detection. The device mainly comprises a vibration isolation plate, a bearing platform with a pressure measuring hole, a linear air floating guide rail, an arc-shaped air floating guide rail, a double-layer chamber, a labyrinth seal, a static pressure gas bearing, a sensor and a collector. According to the device, the two-dimensional, non-contact and friction-free movement of the bearing platform is realized by combining the air floating guide rail and the labyrinth seal, the pressure measuring hole is driven to be aligned with any position to be measured, and the continuous and complete measurement of the pressure of the bearing surface is completed. An inner-layer cavity of the device is used for containing supercritical carbon dioxide and a hydrostatic bearing; compressed air is introduced into the outer-layer cavity to form a positive-pressure air barrier, so that a medium in the inner cavity is prevented from leaking to the atmospheric environment. The method solves the problem that a traditional method is limited in measuring points and cannot adapt to the supercritical carbon dioxide medium environment, and can also be used for pressure distribution testing of other high-pressure and special medium hydrostatic bearings.

Description

TECHNICAL FIELD

[0001] The application relates to a gas floating moving bearing surface type supercritical carbon dioxide static pressure thrust bearing pressure distribution measuring device and belongs to the field of gas lubrication and performance detection. BACKGROUND

[0002] Static pressure gas bearings realize motion support by taking pressurized gas as the lubricating medium, have the advantages of no friction or extremely low friction, high precision, high and low temperature resistance, and radiation resistance, and are widely used in high-end equipment fields such as precision engineering, aerospace, and power machinery. A supercritical carbon dioxide dynamic cycle system is an advanced energy conversion system taking supercritical carbon dioxide as a circulating working medium. A supercritical carbon dioxide static pressure bearing directly uses the circulating working medium as the lubricating medium and is an ideal support for the rotating shaft system in the system, but it also correspondingly puts forward an urgent need for performance testing of the supercritical carbon dioxide static pressure bearing.

[0003] Pressure distribution is a key factor determining the performance of static pressure gas bearings. For supercritical carbon dioxide static pressure bearings, the existing static pressure gas bearing pressure distribution testing technology faces the following challenges:

[0004] (1) Single pressure measurement dimension: the traditional method can only obtain discrete point pressure data by opening a small number of pressure measuring holes at fixed positions on the bearing or bearing surface, and cannot reveal the complete distribution of the gas pressure on the bearing surface, making it difficult to comprehensively evaluate the performance of the bearing.

[0005] (2) Unable to adapt to the needs of high-pressure special medium: the working pressure of supercritical carbon dioxide is above 7.4 MPa, and the traditional static pressure gas bearing performance testing platform is directly exposed to the atmospheric environment, and its open structure design cannot maintain the high environmental pressure required by supercritical carbon dioxide.

[0006] (3) Special medium leakage causes safety problems: the traditional static pressure bearing performance testing platform directly discharges the lubricating gas to the atmospheric environment, but the density of supercritical carbon dioxide under high pressure is extremely large, and discharging to the atmosphere will sharply increase the carbon dioxide concentration in the experimental environment, posing a safety risk.

[0007] Therefore, there is an urgent need for a performance testing device that can realize full-field pressure distribution measurement, adapt to high-pressure and special lubricating medium requirements, and ensure absolute safety and reliability during testing, to fill the gap in related technologies. SUMMARY

[0008] The purpose of the present application is a gas floating moving supercritical carbon dioxide static pressure thrust bearing bearing surface pressure distribution measuring device and its use method, which realizes the unity of full-field pressure distribution measurement, high-pressure working environment maintenance, and special medium leakage blocking in bearing performance detection.

[0009] In order to achieve the object of the present application, the following technical solutions are adopted:

[0010] 1. The present application at least comprises: a data collector, a connecting line, a displacement sensor, a pressure sensor, a test platform, a vibration isolation plate, a linear air floating guide rail, an arc air floating guide rail, a bearing platform, a side support, a distance adjusting base, a distance adjusting screw, a crossbeam, a feeding device, a screw rod, a feeding device transmission nut, a sleeve, a chamber support, a force sensor, an outer layer air pressure sensor, an inner layer air pressure sensor, a bearing support nut, a cover plate, a sealing ring, a bearing support, a static pressure gas bearing, a double-layer chamber, an inner chamber air inlet connector, an inner chamber air outlet connector, an outer chamber air inlet connector, and an outer air pipe seal, characterized in that: the vibration isolation plate and the side support are fixed on a marble platform, the bearing platform is fixed on the linear air floating guide rail, the linear air floating guide rail is fixed on the arc air floating guide rail, the arc air floating guide rail is fixed on the vibration isolation plate, the distance adjusting base is fixed on the side support, the cover plate, the sealing ring, the air inlet and outlet connectors, and the outer air pipe seal are fixed on the double-layer chamber, the outer layer air pressure sensor and the inner layer air pressure sensor are fixed on the cover plate, the double-layer chamber is fixed on the chamber support, the chamber support is connected to the distance adjusting base by the distance adjusting screw, the static pressure gas bearing is fixed on the bearing support, the bearing support is connected to the force sensor by the bearing support nut, the crossbeam is fixed on the side support, the feeding device is sleeved on the screw rod, the screw rod passes through the sleeve and is connected to the force sensor by the feeding device transmission nut, and the displacement sensor and the pressure sensor are fixed on the bottom of the bearing platform and are connected to the data collector by a hose.

[0011] The center points of the feeding device, the screw rod, the sleeve, and the static pressure gas bearing are on the same horizontal line, and the bearing support is adjusted to be horizontal by the distance adjusting screw.

[0012] The double-layer chamber needs to be operated to leave a certain working gap between the bottom of the double-layer chamber and the bearing platform during work.

[0013] The inner and outer layers of the bottom of the double-layer chamber are both provided with a labyrinth seal, which can effectively prevent gas leakage in the working state.

[0014] The linear air floating guide rail and the arc air floating guide rail are non-contact sliding rails lubricated by gas, which can reduce the friction generated during position adjustment.

[0015] The arc air floating guide rail is used for the linear air floating guide rail, so that the linear air floating guide rail can rotate in the Z-axis direction, and the linear air floating guide rail is used for the bearing platform, so that the bearing platform can move along the X-axis direction.

[0016] The bearing platform has two degrees of freedom, the first degree of freedom is that the linear air floating guide rail directly drives the bearing platform to move along the X-axis, and the second degree of freedom is that the arc air floating guide rail drives the linear air floating guide rail to rotate around the Z-axis to adjust the X-axis degree of freedom direction of the linear air floating guide rail to obtain the second degree of freedom.

[0017] The use method of the present application is as follows:

[0018] The first step is to start the device, adjust the arc-shaped air floating guide rail and the linear air floating guide rail to make the displacement sensor and the pressure sensor fixed at the bottom of the bearing platform reach the required position at the bottom of the static pressure gas bearing, the second step is to rotate the feeding device and observe the displacement sensor to reach the required air film thickness, then adjust the distance adjusting screw to make the double-layer chamber bottom leave a certain working gap with the bearing platform, the third step is to test the dry air in the outer chamber of the double-layer chamber, and observe whether the value of the outer air pressure sensor is stable, if not qualified, the distance adjusting screw is adjusted again until the value of the outer air pressure sensor is stable to the required value, the fourth step is to test the supercritical carbon dioxide gas in the inner chamber of the double-layer chamber, and observe whether the value of the inner air pressure sensor reaches the required working condition, if not qualified, the distance adjusting screw is adjusted again and the third step is repeated until the value of the outer air pressure sensor is stable and the value of the inner air pressure sensor reaches the required working condition, and the fifth step is the air test, through the data collector, the values detected by the displacement sensor and the pressure sensor and the bearing capacity, pressure fluctuation and vibration of the static pressure gas bearing under the gas supply pressure obtained by the observation force sensor can be obtained.

[0019] The beneficial effects of the present application are as follows:

[0020] (1) High precision and flexibility: the air floating mobile platform has little friction and high movement precision, which ensures the accuracy of measurement and positioning; the two-dimensional movement mode makes the measurement path and point density flexible, which adapts to different research needs.

[0021] (2) Breakthrough in measurement capacity: the static pressure thrust bearing load surface pressure distribution realizes the qualitative change from "discrete point measurement" to "full-field scanning measurement", and the data is comprehensive, which provides strong support for theoretical research and design optimization.

[0022] (3) Adaptability to high-pressure environment: the overall structure and sealing design are specially designed for high-pressure media such as supercritical carbon dioxide, which can safely and stably maintain the required supercritical high-pressure test environment.

[0023] (4) Safety and cleanliness in the measurement process: the double-cavity structure and the positive pressure air barrier design physically prevent the leakage of working medium to the external environment, which causes personnel, equipment and environmental safety problems.

[0024] The core innovative technical scheme of the present application includes the following three-layer progressive structure:

[0025] The air floating mobile two-dimensional measurement platform is composed of an arc-shaped air floating guide rail and a linear air floating guide rail, forming a two-dimensional frictionless and high-precision movement platform. The bearing platform moves and rotates in the horizontal plane through the driving system, so that the pressure measuring hole can accurately align with any position under the bearing load surface, thereby realizing full-field point-by-point scanning measurement of the pressure distribution.

[0026] The high-pressure sealed main test chamber consists of an inner sealed cavity and a support platform, primarily used to contain hydrostatic bearings and supercritical carbon dioxide media. The bottom of the inner sealed cover is connected to the support platform via a labyrinth seal, allowing for slight movement of the support platform while providing a primary seal under high pressure. This ensures that most of the media is contained within the chamber and can be safely disposed of or recycled through a dedicated vent.

[0027] The key to this invention is the double-layer sealing and positive pressure air barrier safety system. An outer sealing cover surrounds the inner sealing cover, forming a nested double-chamber structure. A separate compressed air supply system continuously delivers compressed air at a pressure higher than atmospheric pressure but lower than the inner test pressure (e.g., 0.2-0.5 MPa gauge pressure) to the outer chamber. This design provides two levels of protection: the inner labyrinth seal blocks most of the supercritical carbon dioxide; if a trace amount of supercritical carbon dioxide permeates the inner seal, it will leak into the outer chamber and be enveloped and diluted by the continuously flowing positive pressure compressed air. Because the pressure in the outer chamber is higher than atmospheric pressure, a stable pressure gradient barrier is formed from the inside out (high pressure of supercritical carbon dioxide → positive pressure of compressed air → atmosphere), fundamentally preventing the escape of the test medium into the atmosphere and achieving intrinsic safety. Attached image description:

[0028] Figure 1 An oblique view of the present invention is shown.

[0029] Figure 2 The diagram illustrates the front view of the present invention.

[0030] Figure 3 A partial exploded view of the present invention is shown.

[0031] Figure 4 A partially enlarged view of the present invention is shown.

[0032] Figure 5 A partially enlarged view of the present invention is shown.

[0033] Figure 6 An enlarged view of a partial feature of the part of the present invention is shown.

[0034] Figure 7 A schematic diagram illustrating the workflow of the present invention is provided.

[0035] 1. Data acquisition unit; 2. Connecting cable; 3. Displacement sensor; 4. Pressure sensor; 5. Test platform; 6. Vibration isolation plate; 7. Linear air-bearing guide rail; 8. Arc-shaped air-bearing guide rail; 9. Bearing platform; 10. Side support; 11. Adjustable base; 12. Adjustable screw; 13. Crossbeam; 14. Feed device; 15. Lead screw; 16. Feed device transmission nut; 17. Sleeve; 18. Chamber support; 19. Force sensor; 20-1. Outer pressure detector; 20-2. Inner pressure detector; 21. Bearing support nut; 22. Cover plate; 23. Sealing ring; 24. Bearing support; 25. Static pressure gas bearing; 26. Double-layer chamber; 27-1. Inner chamber gas inlet connector; 27-2. Inner chamber gas outlet connector; 27-3. Outer chamber gas inlet connector; 28. External gas pipe seal. Detailed implementation method:

[0036] The specific working process of the present invention will be described below with reference to the accompanying drawings.

[0037] The vibration isolation plate 6 and side bracket 10 of this invention are fixed on the test platform 5. The bearing platform 9 is fixed on the linear air-bearing guide rail 7. The linear air-bearing guide rail 7 is fixed on the arc-shaped air-bearing guide rail 8. The arc-shaped air-bearing guide rail 8 is fixed on the vibration isolation plate 6. The adjustable base 12 is fixed on the side bracket 10. The cover plate 22, sealing ring 23, inner cavity gas inlet connector 27-1, inner cavity gas outlet connector 27-2, outer cavity gas inlet connector 27-3, and outer air pipe seal 28 are fixed on the double-layer chamber 26. The outer layer air pressure detector 20-1 and inner layer air pressure detector 20-2 are fixed on the cover plate 26. On plate 22, double-layer chamber 26 is fixed on chamber support 18. Chamber support 18 is connected to adjustable base 11 by adjustable screw 12. Static pressure gas bearing 25 is fixed on bearing support 24. Bearing support 24 is connected to force sensor 19 by bearing support nut 21. Crossbeam 13 is fixed on side support 10. Feed device 14 is sleeved on lead screw 15. Lead screw 15 passes through sleeve and is connected to force sensor 19 by feed device transmission nut 16. Displacement sensor 3 and temperature sensor 4 are fixed at the bottom of bearing platform 9 and connected to data acquisition unit 1 by hose 2.

[0038] First, start the device and adjust the arc-shaped air-bearing guide rail 21 and the linear air-bearing guide rail 20 so that the displacement sensor 3 and pressure sensor 4, fixed at the bottom of the bearing platform 9, reach the required position at the bottom of the static pressure gas bearing 25. Second, rotate the feed device 14 and observe the reading of the displacement sensor 3 to reach the required air film thickness. Then, adjust the pitch screw 12 to leave a certain working gap between the bottom of the double-layer chamber 26 and the bearing platform 9. Third, test-pass dry air through the outer chamber of the double-layer chamber 26 and observe whether the value of the outer air pressure sensor 20-1 is stable. If it is not qualified, readjust the pitch screw 12 until the outer layer is stable. The fourth step involves purging the inner layer of the double-layer chamber 26 with supercritical carbon dioxide gas and observing whether the value of the inner layer pressure sensor 20-2 reaches the required operating condition. If it fails, adjust the adjusting screw 12 and repeat the third step until the value of the outer layer pressure sensor 20-1 stabilizes and the inner layer pressure sensor 20-2 reaches the required operating condition. The fifth step is a ventilation test. The data acquisition device 1 can obtain the values ​​detected by the displacement sensor 3 and the pressure sensor 4, and observe the load-bearing capacity, pressure fluctuation and vibration of the static pressure gas bearing 25 under the gas supply pressure obtained by the force sensor 19.

Claims

1. A gas-float mobile bearing surface supercritical carbon dioxide hydrostatic thrust bearing pressure distribution measurement apparatus comprising: The utility model relates to a data acquisition device, connecting line (2), displacement sensor (3), pressure sensor (4), experimental platform (5), vibration isolation board (6), straight line air float guide rail (7), arc air float guide rail (8), bearing platform (9), side support (10), distance adjusting base (11), distance adjusting screw (12), crossbeam (13), feeding device (14), screw rod (15), feeding device transmission nut (16), sleeve (17), chamber support (18), force sensor (19), outer layer pressure sensor (20-1), inner layer pressure sensor (20-2), bearing support nut (21), cover plate (22), sealing ring (23), bearing support (24), static pressure gas bearing (25), double -layer chamber (26), inner cavity gas inlet connector (27-1), inner cavity gas outlet connector (27-2), outer cavity gas inlet connector (27-3), outer gas pipe seal (28), its characterized in that: vibration isolation board (6), side support (10) are fixed on experimental platform (5), bearing platform (9) is fixed on straight line air float guide rail (7), straight line air float guide rail (7) is fixed on arc air float guide rail (8), arc air float guide rail (8) is fixed on vibration isolation board (6), distance adjusting base (12) is fixed on side support (10), cover plate (22), sealing ring (23), inner cavity gas inlet connector (27-1), inner cavity gas outlet connector (27-2), outer cavity gas inlet connector (27-3), outer gas pipe seal (28) are fixed on double -layer chamber (26), outer layer pressure sensor (20-1) and inner layer pressure sensor (20-2) are fixed on cover plate (22), double -layer chamber (26) is fixed on chamber support (18), chamber support (18) is connected on distance adjusting base (11) by distance adjusting screw (12), static pressure gas bearing (25) is fixed on bearing support (24), bearing support (24) is connected on force sensor (19) by bearing support nut (21), crossbeam (13) is fixed on side support (10), feeding device (14) is sleeved on screw rod (15), screw rod (15) passes through sleeve and is connected on force sensor (19) by feeding device transmission nut (16), displacement sensor (3), pressure sensor (4) are fixed on bearing platform (9) bottom and are connected data acquisition device (1) by connecting line (2).

2. The floating supercritical carbon dioxide hydrostatic thrust bearing pressure distribution measurement device of claim 1, wherein: The center points of the feeding device (14), the screw rod (15), the sleeve (17) and the static pressure gas bearing (25) are on the same horizontal line, and the bearing support (24) is adjusted to be horizontal by the distance adjusting screw (12).

3. The floating supercritical carbon dioxide hydrostatic thrust bearing pressure distribution measurement device of claim 1, wherein: The double -layer chamber (26) needs to operate the distance adjusting screw (12) to leave about one millimeter working gap between the bottom of the double -layer chamber (26) and the bearing platform (9) during work.

4. The floating supercritical carbon dioxide hydrostatic thrust bearing pressure distribution measurement device of claim 1, wherein: The bottom of the double -layer chamber (26) is provided with a labyrinth seal, which can effectively prevent gas leakage in the working state.

5. A device for measuring the performance of a gas-lubricated moving bearing surface type thrust bearing with pressurized static pressure according to claim 1, characterized in that: The straight line air float guide rail (7) and the arc air float guide rail (8) are non -contact sliding rails lubricated by gas, which can reduce the friction generated during position adjustment.

6. The floating supercritical carbon dioxide hydrostatic thrust bearing pressure distribution measurement device of claim 1, wherein: The arc-shaped air floating guide rail (8) is used for the linear air floating guide rail (7) to enable the linear air floating guide rail (7) to rotate in the Z-axis direction, and the linear air floating guide rail (7) is used for the bearing platform (9) to enable the bearing platform (9) to move in the X-axis direction.

7. The floating supercritical carbon dioxide hydrostatic thrust bearing pressure distribution measurement device of claim 6, wherein: The bearing platform (9) has two degrees of freedom, the first degree of freedom is that the linear air floating guide rail (7) directly drives the bearing platform (9) to move in the X-axis direction, and the second degree of freedom is that the arc-shaped air floating guide rail (8) drives the linear air floating guide rail (7) to rotate around the Z-axis to obtain the second degree of freedom in the X-axis direction of the linear air floating guide rail (7).

8. The method of using a gas floatation moving load plane type supercritical carbon dioxide static pressure thrust bearing pressure distribution measuring device according to claim 7, characterized in that: The first step is to start the device, adjust the arc-shaped air floating guide rail (8) and the linear air floating guide rail (7) to enable the displacement sensor (3) and the pressure sensor (4) fixed at the bottom of the bearing platform (9) to reach the required position at the bottom of the static pressure gas bearing (25), the second step is to rotate the feeding device (14) and observe the displacement sensor (3) to reach the required air film thickness, then adjust the distance adjusting screw (12) to enable the double-layer chamber (26) to leave a certain working gap with the bearing platform (9), the third step is to pass dry air through the outer layer, and observe whether the value of the outer layer air pressure sensor (20-1) is stable, if not qualified, adjust the distance adjusting screw (12) until the value of the outer layer air pressure sensor (20-1) is stable to the required value, the fourth step is to pass supercritical carbon dioxide gas through the inner layer, and observe whether the value of the inner layer air pressure sensor (20-2) reaches the required working condition, if not qualified, adjust the distance adjusting screw (12) and repeat the third step until the value of the outer layer air pressure sensor (20-1) is stable and the value of the inner layer air pressure sensor (20-2) reaches the required working condition, and the fifth step is a gas test, through the data collector (1), the values detected by the displacement sensor (3) and the pressure sensor (4) and the bearing force, pressure fluctuation and vibration of the static pressure gas bearing (25) under the gas supply pressure obtained by the observation force sensor (19) can be obtained.

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