Oil-gas separation combined structure of bearing cavity

Abstract

The invention provides a bearing cavity oil-gas separation combined structure which comprises a high-low pressure shaft, a rotary oil slinger, a rotary separator and a stator defoamer, and a rotary oil slinger and the rotary separator are arranged outside the low-pressure shaft and the high-pressure shaft respectively and rotate at different rotating speeds; the stator defoamer is arranged on the radial outer side of the rotary oil throwing cup and the rotary separator and completely wraps the rotary oil throwing cup and the rotary separator. By means of the structure, separation of lubricating oil and air is achieved, the recycling efficiency of the lubricating oil and the purification degree of sealing gas are improved, and the device has important significance on reducing the lubricating oil consumption of an aero-engine and improving reliability.

Description

Technical Field

[0001] The present invention relates to the technical field of aeroengines, and particularly to an oil-gas separation combined structure for a bearing cavity. Background Art

[0002] The characteristics of high rotational speed, high mainstream temperature, and strong maneuverability of aeroengines make the rotor support bearings face complex working conditions such as high DN value, high temperature, and large load. A large amount of lubricating oil must be supplied to lubricate and cool the bearings. At the same time, in order to ensure that the lubricating oil does not leak from the rotating-stationary seal of the bearing cavity into other parts of the engine, a sealing gas needs to be provided to seal the bearing cavity. Therefore, the bearing cavity is filled with a mixture of lubricating oil and air, and due to the rotation of the rotor, most of the lubricating oil is in an atomized state. The above characteristics in the bearing cavity cause two problems: one is that the atomized lubricating oil makes it difficult to recover the lubricating oil, and even a large amount of lubricating oil bubbles will be generated under the purging action of the air, further increasing the difficulty of lubricating oil recovery; the other is that the air containing atomized lubricating oil will cause lubricating oil coking after encountering a high-temperature metal wall surface during the continuous flow process. The coked lubricating oil adheres to the metal wall surface, especially after adhering to the rotating wall surface, it will damage the dynamic balance of the rotor, causing problems such as large vibration.

[0003] How to arrange a structure in the narrow space of the bearing cavity to achieve the separation of lubricating oil and air, and improve the recovery efficiency of lubricating oil and the purification degree of the sealing gas is of great significance for reducing the lubricating oil consumption of aeroengines and improving reliability. Summary of the Invention

[0004] In view of this, the present invention provides an oil-gas separation combined structure for a bearing cavity, so as to achieve the analysis of the oil-gas mixture in a compact bearing cavity, and the purpose of improving the recovery efficiency of lubricating oil and the purification degree of the sealing gas can be achieved.

[0005] The present invention provides the following technical solutions: An oil-gas separation combined structure for a bearing cavity includes a high-pressure shaft 11 and a low-pressure shaft 12. A rotating oil throwing ring 7 is sleeved outside the low-pressure shaft 12, and the low-pressure shaft 12 can drive the rotating oil throwing ring 7 to rotate at a first speed; a rotating separator 9 is sleeved outside the high-pressure shaft 11, and the high-pressure shaft 11 can drive the rotating separator 9 to rotate at a second speed, and the first speed is less than the second speed; a stator defoamer 8 is arranged on the radial outside of the rotating oil throwing ring 7 and the rotating separator 9.

[0006] Further, the rotating separator 9 is arranged on the radial outside of the rotating oil throwing ring 7, and one end of the rotating separator 9 partially overlaps with one end of the rotating oil throwing ring 7 in the axial direction.

[0007] Further, the axial installation length of the rotating oil throwing ring 7 and the rotating separator 9 is a first length, and the axial length of the stator defoamer 8 is greater than the first length.

[0008] Further, the stator defoamer 8 is provided with a plurality of defoaming through-holes that are spaced apart along the axial direction.

[0009] Further, the axis of the defoaming through-hole is inclined with respect to the wall surface of the stator defoamer 8, and the inclination direction of the axis of the defoaming through-hole is opposite to the rotation direction of the high-pressure shaft 11.

[0010] Further, the high-pressure shaft 11 and the low-pressure shaft 12 are spaced apart in the radial direction, and a high-low pressure shaft intermediate air flow path 10 is formed between the high-pressure shaft 11 and the low-pressure shaft 12. The air purified by the rotating oil slinger 7, the rotating separator 9, and the stator defoamer 8 is discharged through the high-low pressure shaft intermediate air flow path 10.

[0011] Further, the rotating separator 9 is a rotary barrel-shaped structure, and a plurality of spaced-apart separation through-holes are provided on the barrel wall of the rotating separator 9.

[0012] Further, the inner wall of the rotating separator 9 is provided with a plurality of stepped structures that protrude radially inward, and along the direction away from the connection end of the rotating separator 9 and the high-pressure shaft 11, the inner diameters of the plurality of stepped structures gradually increase.

[0013] Further, the outer wall of the rotating oil slinger 7 has a tooth structure that protrudes radially outward, and along the direction away from the connection end of the rotating oil slinger 7 and the low-pressure shaft 12, the outer diameters of the plurality of tooth structures gradually decrease.

[0014] Compared with the prior art, the at least one technical solution adopted by the present invention can achieve at least the following beneficial effects: adopting a combined structure of oil and gas separation in the bearing chamber to achieve efficient separation of lubricating oil and air in the bearing chamber, while achieving improvement in lubricating oil recovery efficiency and seal gas purification degree, which is of great significance for reducing the lubricating oil consumption of aeroengines and improving reliability. The rotating oil slinger and the rotating separator are located inside the bearing chamber and can be integrally designed with other parts such as nuts and spacer rings on the rotor, without increasing the number of parts and without increasing the external dimensions of the engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0016] Figure 1 It is a schematic structural diagram of an embodiment of the present invention.

[0017] Reference numerals in the drawings: 1, high-pressure rotor support bearing; 2, low-pressure rotor support bearing; 3, high-pressure bearing oil supply flow path; 4, low-pressure bearing oil supply flow path; 5, left-side rotating-stationary seal of bearing cavity; 6, right-side rotating-stationary seal of bearing; 7, rotating oil slinger; 8, stator defoamer; 9, rotating separator; 10, high-low pressure shaft intermediate air flow path; 11, high-pressure shaft; 12, low-pressure shaft. Detailed implementation manners

[0019] The embodiments of the present application will be described in detail below with reference to the drawings.

[0020] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the drawings and in combination with the embodiments.

[0021] Figure 1 It is a schematic diagram of a combined structure for oil-gas separation in a bearing cavity, including a rotating oil slinger 7, a stator defoamer 8, a rotating separator 9, a high-pressure shaft 11 and a low-pressure shaft 12. The rotating oil slinger 7 is sleeved outside the low-pressure shaft 12 and rotates at a first speed. The rotating separator 9 is sleeved outside the high-pressure shaft and rotates at a second speed, and the first speed is less than the second speed. The axial length of the stator defoamer 8 is greater than the sum of the rotating oil slinger 7 and the rotating separator 9, and can completely wrap the two.

[0022] In the embodiment of the present invention, by setting the rotating oil slinger 7, the stator defoamer 8 and the rotating separator 9, the huge differences in physical properties such as viscosity and density between the lubricating oil and the air can be utilized, and the two can be separated by centrifugal force: the rotating oil slinger 7 rotating at a high speed throws out the lubricating oil-air mixture (mainly the lubricating oil with a large density). The oil-gas mixture preliminarily separated by the rotating oil slinger 7 further enters the rotating rotating separator 9 for separation. The mist-like lubricating oil flying out at a high speed due to the centrifugal force will converge on the inner wall surface of the stator defoamer 8 after contacting the stator defoamer 8 and flow out from the small holes of the stator defoamer 8 and flow to the bottom oil return hole under the action of gravity. The above structure realizes the analysis of the oil-gas mixture in a compact bearing cavity, can improve the recovery efficiency of the lubricating oil, reduce the lubricating oil consumption of the aero-engine and improve the reliability.

[0023] It should be noted that the rotating speeds of the rotating oil slinger 7 and the rotating separator 9 are inconsistent, and rotating at different speeds can achieve a better comprehensive separation effect; secondly, the axial length of the stator defoamer 8 is greater than the axial installation lengths of the rotating oil slinger 7 and the rotating separator 9, which can enable the stator defoamer 8 to completely wrap them, so that all the thrown mist-like lubricating oil can be converged through the stator defoamer 8.

[0024] The stator defoamer 8 in this example is provided with a plurality of defoaming holes spaced apart in the axial direction, so that the thrown-out lubricating oil can be gathered on the inner wall and flow out through the holes; the axis of the defoaming hole is inclined to the wall of the stator defoamer 8, and the inclination direction of the axis of the defoaming hole is opposite to the rotation direction of the high-pressure shaft 11, thereby improving the flow characteristics of the fluid and eliminating or reducing the influence of bubbles on the system performance.

[0025] In this example, the rotating oil slinger 7 and the rotating separator 9 are the main lubricating oil separation structures, which partially overlap in the axial direction to form an oil relay to ensure that the target parts are covered and avoid oil splashing and waste or insufficient lubrication. At the same time, the outer wall of the rotating oil slinger 7 protrudes radially outward, and along the direction away from the connection end of the rotating oil slinger 7 and the low-pressure shaft 12, the outer diameter of the multiple protruding tooth structures gradually decreases, and the inner wall of the rotating separator 9 is provided with multiple step structures protruding radially inward, and along the direction away from the connection end of the rotating separator 9 and the high-pressure shaft 11, the inner diameter of the multiple step structures gradually increases; the two structures are connected, and when rotating at high speed, the protruding teeth with decreasing outer diameters produce a gradually weakening centrifugal force, so that large oil droplets are preferentially thrown out at the larger outer diameter end, and small oil droplets are further separated at the smaller outer diameter end, and the separator gradually expands The structure forms a gradually increasing interception area, which matches the centrifugal field gradient of the oil slinger cup, ensuring that oil droplets of different particle sizes can be effectively intercepted.

[0026] Furthermore, the rotary separator 9 is a rotary barrel structure, and a plurality of separation through holes distributed at intervals are arranged on the barrel wall of the rotary separator 9, and an inner step is arranged to block the direct route of the oil-gas mixture, so that the oil and gas enter the rotary hole for further separation.

[0027] In this example, the high-pressure bearing oil supply flow path 3 and the low-pressure bearing oil supply flow path 4 supply lubricating oil to the high-pressure rotor support bearing 1 and the low-pressure rotor support bearing 2 respectively to ensure lubrication and cooling of the bearings during complex operation. However, in order to ensure that the lubricating oil does not leak from the bearing cavity rotary-static seal into other parts of the engine, it is necessary to provide sealing gas to seal the bearing cavity. The rotary-static seal 5 on the left side of the bearing cavity and the rotary-static seal 6 on the right side of the bearing in the figure play a good role. At the same time, the high-pressure shaft 11 and the low-pressure shaft 12 are spaced apart in the radial direction, and a high- and low-pressure shaft air flow path 10 is formed between the high-pressure shaft 11 and the low-pressure shaft 12. The purified air after passing through the rotating oil slinger 7, the rotating separator 9 and the stator defoamer 8 is discharged through the high- and low-pressure shaft air flow path 10, which can effectively improve the purification degree of the sealing gas.

[0028] As described above, only the specific embodiments of the present invention are provided, and the scope of the invention cannot be limited thereby. Therefore, the replacement of equivalent components, or equivalent changes and modifications made in accordance with the scope of protection of the present invention, should still fall within the scope covered by this patent. In addition, the technical features, technical features and technical solutions, and technical solutions and technical solutions in the present invention can be freely combined and used.

Claims

1. A combined oil-gas separation structure for a bearing cavity, comprising a high-pressure shaft (11) and a low-pressure shaft (12), characterized in that, The oil-gas separation combined structure of the bearing cavity further includes: A rotating oil slinger (7) sleeved outside the low-pressure shaft (12), and the low-pressure shaft (12) can drive the rotating oil slinger (7) to rotate at a first speed; A rotating separator (9) sleeved outside the high-pressure shaft (11), and the high-pressure shaft (11) can drive the rotating separator (9) to rotate at a second speed, and the first speed is less than the second speed; A stator defoamer (8) arranged on the radial outer side of the rotating oil slinger (7) and the rotating separator (9).

2. The oil-gas separation combined structure of the bearing cavity according to claim 1, wherein The rotating separator (9) is arranged on the radial outer side of the rotating oil slinger (7), and one end of the rotating separator (9) partially overlaps with one end of the rotating oil slinger (7) in the axial direction.

3. The oil-gas separation combined structure of the bearing cavity according to claim 2, characterized in that, The axial installation lengths of the rotating oil slinger (7) and the rotating separator (9) are a first length, and the axial length of the stator defoamer (8) is greater than the first length.

4. The oil-gas separation combined structure of the bearing cavity according to claim 3, characterized in that, The stator defoamer (8) is provided with a plurality of spaced-apart defoaming through holes in the axial direction.

5. The oil-gas separation combined structure of the bearing cavity according to claim 4, wherein The axis of the defoaming through hole is inclined with respect to the wall surface of the stator defoamer (8), and the inclination direction of the axis of the defoaming through hole is opposite to the rotation direction of the high-pressure shaft (11).

6. The oil-gas separation combined structure of the bearing cavity according to claim 1, characterized in that The high-pressure shaft (11) and the low-pressure shaft (12) are spaced apart in the radial direction, and a high-low pressure shaft intermediate air flow path (10) is formed between the high-pressure shaft (11) and the low-pressure shaft (12), and the air purified after passing through the rotating oil slinger (7), the rotating separator (9) and the stator defoamer (8) is led out through the high-low pressure shaft intermediate air flow path (10).

7. The oil-gas separation combined structure of the bearing cavity according to claim 1, characterized in that The rotating separator (9) is of a rotary barrel structure, and a plurality of spaced-apart separation through holes are provided on the barrel wall of the rotating separator (9).

8. The oil-gas separation combined structure of the bearing cavity according to claim 7, wherein The inner wall of the rotating separator (9) is provided with a plurality of radially inwardly protruding stepped structures, and along the direction away from the connection end of the rotating separator (9) and the high-pressure shaft (11), the inner diameters of the plurality of stepped structures gradually increase.

9. The oil-gas separation combined structure of the bearing cavity according to claim 1, characterized in that The outer wall of the rotating oil slinger (7) has radially outwardly protruding tooth structures, and along the direction away from the connection end of the rotating oil slinger (7) and the low-pressure shaft (12), the outer diameters of the plurality of tooth structures gradually decrease.

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