Damping structure, working method of damping structure and engine rotor system

Abstract

The invention relates to the technical field of aero-engines, and discloses a damping structure, a working method of the damping structure and an engine rotor system.The damping structure comprises a bush body, an outer ring, a bearing body, an inner ring and an inner ring, a plurality of boss parts are arranged on the side, facing the bearing body in the radial direction, of the bush body, and mounting grooves are formed between every two adjacent boss parts at intervals in the axial direction. The damping ring is mounted in the mounting groove, and the boss part is suitable for limiting the axial displacement of the damping ring; the damping ring is made of viscoelastic materials, and the side, facing the bearing body in the radial direction, of the damping ring elastically abuts against the outer ring of the bearing body, so that an extrusion gap is formed between the outer ring of the bearing body and the inner side circumferential wall of the bush body in the radial direction at intervals. According to the damping structure provided by the invention, an oil supply device and an oil supply path do not need to be arranged, the initial compression amount of the damping ring can be changed by changing the depth of the mounting groove, or by changing the hardness of the damping ring, the effect of adjusting the bearing rigidity so as to adjust the critical rotating speed of the rotor is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of aeroengines, and in particular to a damping structure, a working method of the damping structure and an engine rotor system. Background Art

[0002] The engine life of strategic missiles is very short, and they are usually simple to manufacture, low cost, and high efficiency. As an important vibration reduction component of the engine rotor system, the damper should be designed and manufactured in accordance with the engine. At present, aircraft engines mainly use traditional squeeze film dampers (Servo Fluid Damper, SFD) for vibration reduction, but the squeeze film damper requires an additional oil supply system, occupies a large space, has a complex structure, and has a high manufacturing cost, which is not suitable for use in short-life, low-cost engines. Summary of the invention

[0003] In view of this, the present invention provides a damping structure, a working method of the damping structure and an engine rotor system to solve the problem that the current aircraft engine uses a squeeze film damper, which requires an additional oil supply system, occupies a large space, has a complex structure, and has a high manufacturing cost, and is not suitable for application in short-life, low-cost engines.

[0004] In a first aspect, the present invention provides a damping structure, comprising:

[0005] The bushing body is sleeved on the outer ring of the bearing body;

[0006] A plurality of bosses are provided on one side of the bushing body facing the bearing body in the radial direction, and mounting grooves are formed between two adjacent bosses in the axial direction.

[0007] The damping ring is installed in the installation groove, and the boss portion is suitable for limiting the axial displacement of the damping ring; the damping ring is made of viscoelastic material, and the damping ring elastically abuts against the outer ring of the bearing body along the radial side facing the bearing body, and an extrusion gap is formed between the outer ring of the bearing body and the inner peripheral wall of the bushing body along the radial interval.

[0008] Beneficial effects: The damping structure provided by the present invention, on the one hand, replaces the oil film gap of the squeeze film damper by the squeeze gap formed between the outer ring of the bearing body and the bushing body, and at the same time, the damping ring plays a centering and supporting role, replacing the elastic support in the squeeze film damper, and does not need to set an oil supply device and an oil supply hole and an oil supply path such as an oil supply hole, and the weight of the damping ring is lighter, which greatly reduces the weight of the structure, reduces the manufacturing cost, is conducive to improving the thrust-to-weight ratio of the engine, and is more suitable for the elastic support design of the rotor system of a short-life, low-cost engine. On the other hand, when the rotor is subjected to unbalanced force and vibrates during high-speed rotation, the vibration load is transmitted to the outer ring of the bearing body through the journal, and the outer ring of the bearing body squeezes the damping ring and does work on the damping ring. During the deformation process, the viscoelastic damping of the damping ring is used to convert part of the vibration energy into internal energy consumption, and when the rotor exceeds the critical speed, the unbalanced response of the rotor can be effectively suppressed, and the stability of the rotor system can be improved; compared with the squeeze film damper, there will be no collision and friction caused by the nonlinearity of the oil film force; even if the rotor tapers, stable damping can be provided, and the vibration reduction effect and reliability are better. On the other hand, the oil film stiffness of the squeeze film damper is nonlinear, and the support stiffness must be adjusted by relying on squirrel cage elastic support; the damping structure of the present invention can change the initial compression of the damping ring by changing the depth of the mounting groove on the bushing body, or by changing the hardness of the damping ring, thereby adjusting the support stiffness and thus adjusting the critical speed of the rotor. The damping ring can also be centered, and there is no need to add additional squirrel cage elastic support, which simplifies the structure and reduces the weight.

[0009] In an optional embodiment, a transition portion is formed between the boss portion and the inner peripheral wall of the bushing body by chamfering, and the transition portion is suitable for smoothly abutting against the damping ring.

[0010] Beneficial effect: thus preventing the damping ring from experiencing stress concentration during the extrusion process and avoiding damage to the damping ring.

[0011] In an optional embodiment, the mounting groove is a dovetail groove structure; the boss portion forms a convex angle on the side close to the damping ring along the axial direction, and the convex angle is set at an acute angle with the inner peripheral wall of the bushing body, and the convex angle is suitable for limiting the damping ring.

[0012] Beneficial effect: The installation groove adopts a dovetail groove structure. On the one hand, the convex corner of the dovetail groove structure can be used to clamp the damping ring, thereby facilitating the installation of the damping ring. On the other hand, the convex corner is set at an acute angle to the inner peripheral wall of the bushing body, which can make the wall surface of the installation groove shrink outward to form a conical wall surface. When the damping ring is compressed and deformed, the outward contracted wall surface will provide a constraint, thereby increasing the friction damping between the damping ring and the conical wall surface.

[0013] In an optional embodiment, the damping ring is interference fit with the outer ring of the bearing body.

[0014] Beneficial effect: In order to prevent the damping ring from loosening, the inner diameter of the damping ring can be made slightly smaller than the outer diameter of the bearing body, so that the damping ring is interference-fitted to the outer ring of the bearing body, which is beneficial to improving the fatigue performance of the damping ring.

[0015] In an optional implementation, the number of the damping rings is at least two.

[0016] Beneficial effect: thus ensuring the stability of the engine rotor system.

[0017] In an optional embodiment, the bushing body includes a first bushing, and at least two mounting grooves are arranged on a side of the first bushing radially facing the bearing body. The mounting grooves are arranged on the bushing body at intervals along the axial direction, and a damping ring is arranged in each mounting groove.

[0018] Beneficial effect: The first bushing is formed by axially extending the length of the bushing, and more damping rings are placed by additionally adding mounting grooves on the first bushing, thereby ensuring the stability of the engine rotor system.

[0019] In an optional embodiment, the bushing body includes a second bushing and a third bushing, and the third bushing is arranged between the second bushing and the outer ring of the bearing body; the third bushing is provided with at least one mounting groove along the radial side facing the bearing body, and the second bushing is provided with at least one mounting groove along the radial side facing the third bushing, and a damping ring is provided in each mounting groove.

[0020] Beneficial effect: If the axial dimension of the bushing is limited, the number of bushings can be increased radially to form a second bushing and a third bushing, and mounting grooves can be provided on the additional bushings to place more damping rings, thereby ensuring the stability of the engine rotor system.

[0021] In a second aspect, the present invention further provides a working method of the damping structure as described above, comprising:

[0022] By changing the depth of the installation groove, the initial compression rate of the damping ring is changed to adjust the support stiffness of the damping ring, thereby adjusting the critical speed of the rotor system;

[0023] and / or, by changing the hardness of the damping ring to adjust the support stiffness of the damping ring, thereby adjusting the critical speed of the rotor system;

[0024] Centering and support by damping ring;

[0025] The energy of the vibration is dissipated through the viscoelastic damping of the damping ring.

[0026] Beneficial effects: The working method of the damping structure provided by the present invention changes the initial compression rate of the damping ring by changing the depth of the installation groove, and / or, by changing the hardness of the damping ring, so as to adjust the support stiffness of the damping ring, thereby adjusting the critical speed of the rotor system, and no additional squirrel cage elastic support is required, which is conducive to simplifying the structure and reducing the weight; the damping ring is used for centering and support, and there is no need to set up an oil supply device and an oil supply hole and an oil supply path such as an oil supply hole, and the weight of the damping ring is lighter, which greatly reduces the weight of the structure and reduces the manufacturing cost, which is conducive to improving the thrust-to-weight ratio of the engine, and is more suitable for the rotor system elastic of a short-life, low-cost engine. Flexible support design; the vibratory energy is dissipated by the viscoelastic damping of the damping ring. When the rotor is vibrated by the unbalanced force during high-speed rotation, the vibration load is transmitted to the outer ring of the bearing body through the shaft neck. The outer ring of the bearing body squeezes the damping ring and does work on the damping ring. During the deformation process, the viscoelastic damping of the damping ring is used to convert part of the vibration energy into internal energy consumption. When the rotor exceeds the critical speed, the unbalanced response of the rotor can be effectively suppressed, thereby improving the stability of the rotor system. Compared with the squeeze film damper, there will be no rubbing caused by the nonlinearity of the oil film force. Even if the rotor tapers, it can provide stable damping, and the vibration reduction effect and reliability are better.

[0027] In an optional implementation, changing the hardness of the damping ring includes:

[0028] According to the actual operating temperature of the engine, use the formula H rt =H rst +β(T-23), calculate the change of the damping ring hardness, and then select the damping ring with appropriate hardness, where H rt is the material hardness at ambient temperature T, H rst is the material hardness at standard room temperature, T is the ambient temperature, and β is the temperature correction coefficient.

[0029] Beneficial effect: To determine the appropriate support stiffness range of the damping ring, thereby adjusting the critical speed of the rotor system.

[0030] In a third aspect, the present invention further provides an engine rotor system, comprising: a rotor body, and the damping structure as described above.

[0031] Beneficial effects: The engine rotor system of the third aspect includes the damping structure of the first aspect, and therefore, the engine rotor system of the third aspect includes all the beneficial effects of the damping structure of the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 is a cross-sectional view of a squeeze film damper in the related art;

[0034] Figure 2 is a cross-sectional view of a damping structure according to an embodiment of the present invention;

[0035] Figure 3 A partially enlarged cross-sectional view of a mounting groove of a bushing body of the damping structure of the present invention;

[0036] Figure 4 It is a partial enlarged cross-sectional view of another installation groove of the bushing body of the damping structure of the present invention;

[0037] Figure 5 is a cross-sectional view of another damping structure according to an embodiment of the present invention;

[0038] Figure 6 is a cross-sectional view of another damping structure according to an embodiment of the present invention;

[0039] Figure 7 is a curve diagram showing the change of stiffness versus hardness of the damping ring of the damping structure of the present invention at different initial compression rates;

[0040] Figure 8 It is a test principle diagram of the vibration reduction characteristics of the damping structure of the present invention using a bidirectional excitation tester.

[0041] Description of reference numerals:

[0042] 10. Bushing body; 101. Boss portion; 102. Mounting groove; 103. Extrusion gap; 104. Transition portion; 105. Protruding corner; 11. First bushing; 12. Second bushing; 13. Third bushing;

[0043] 20. Bearing body;

[0044] 30. Damping ring. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are 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 those skilled in the art without creative work are within the scope of protection of the present invention.

[0046] In a high-speed rotating rotor system, due to installation errors and gravity, the rotor's mass center does not coincide with the rotor's rotation axis, resulting in an unbalanced force of fixed direction and magnitude during rotation. This imbalance causes the rotor to vibrate periodically during rotation, which is prone to large vibrations. Secondly, the rotor's mass distribution is uneven during the manufacturing process, which generates an unbalanced force of random direction and magnitude during rotation. If these vibrations are not controlled, it may cause equipment failure or even serious damage.

[0047] At present, squeeze film dampers are widely used in large aircraft engines to reduce rotor vibration. Figure 1 The squeeze film damper shown in the figure has an oil supply hole 801 and an oil supply groove 802 on the metal bushing 80 of the squeeze film damper, and an oil film gap 803 is formed between the inner circumferential wall of the metal bushing 80 and the outer circumferential wall of the bearing. The squeeze film damper needs to be provided with a squirrel cage elastic support 90, and the squirrel cage elastic support 90 is used to adjust the support stiffness, thereby adjusting the critical speed; the space between the rotor and the support device is filled with lubricating oil. When the rotor vibrates, the oil film in the squeeze film damper will be squeezed to generate a damping force, thereby reducing the amplitude of the vibration and reducing the vibration energy of the system.

[0048] Although the squeeze film damper has a significant vibration reduction effect, for short-life, low-cost engines such as strategic missile engines, the squeeze film damper has the following defects: In terms of cost, when using the squeeze film damper for vibration reduction, it is necessary to add an additional oil supply device and design an oil supply path to supply lubricating oil, which increases the weight of the structure, requires higher manufacturing process, and the cost also increases accordingly. Therefore, the squeeze film damper is not suitable for use in short-life, low-cost missile engines; In terms of vibration reduction effect, if the squeeze film damper has a large manufacturing error, or is under severe working conditions such as large load, high speed, sudden imbalance, etc. that exceed its designed working range, the nonlinearity of the oil film force will be greatly increased, which will lead to many harmful nonlinear responses, such as uncoordinated precession of the rotor, bistable jump, and failure to pass the critical speed, which will not only fail to suppress vibration, but also make the vibration more intense; In terms of oil film stability, during the high-speed operation of the rotor, the journal may taper, that is, the axial movement radius is different, resulting in uneven axial distribution of the oil film gap, which will affect the damping effect of the oil film.

[0049] Combine the following Figures 2 to 8 , describing an embodiment of the present invention.

[0050] According to an embodiment of the present invention, on the one hand, a damping structure is provided, comprising:

[0051] The bushing body 10 is made of metal material and is sleeved on the outer ring of the bearing body 20;

[0052] See also Figure 2 As shown, the bushing body 10 is provided with a plurality of bosses 101 on one side radially facing the bearing body 20, and a mounting groove 102 is formed between two adjacent bosses 101 along the axial direction;

[0053] The damping ring 30 is installed in the installation groove 102, so as to save the space occupied by the damping ring 30; the boss portion 101 is suitable for limiting the axial displacement of the damping ring 30; the damping ring 30 is made of viscoelastic material, and the damping ring 30 elastically abuts against the outer ring of the bearing body 20 along the side radially facing the bearing body 20, so that an extrusion gap 103 is formed between the outer ring of the bearing body 20 and the inner peripheral wall of the bushing body 10 along the radial interval.

[0054] The damping structure provided by the present invention, on the one hand, replaces the oil film gap of the squeeze film damper with the extrusion gap 103 formed between the outer ring of the bearing body 20 and the bushing body 10, and at the same time, the damping ring 30 plays a centering and supporting role, replacing the elastic support in the squeeze film damper. There is no need to set up an oil supply device and oil supply holes and oil supply paths such as oil supply holes. In addition, the damping ring 30 is lighter, which greatly reduces the weight of the structure and reduces the manufacturing cost, which is beneficial to improving the thrust-to-weight ratio of the engine and is more suitable for the elastic support design of the rotor system of short-life, low-cost engines. On the other hand, when the rotor is vibrated by unbalanced force during high-speed rotation, the vibration load is transmitted to the outer ring of the bearing body 20 through the shaft neck. The outer ring of the bearing body 20 squeezes the damping ring 30 and does work on the damping ring 30. During the deformation process, the viscoelastic damping of the damping ring 30 is used to convert part of the vibration energy into internal energy consumption. When the rotor exceeds the critical speed, the unbalanced response of the rotor can be effectively suppressed, thereby improving the stability of the rotor system. Compared with the squeeze film damper, there will be no rubbing caused by the nonlinearity of the oil film force. Even if the rotor tapers, stable damping can be provided, and the vibration reduction effect and reliability are better. On the other hand, the oil film stiffness of the squeeze film damper is nonlinear, and the support stiffness must be adjusted by relying on squirrel cage elastic support; the damping structure of the present invention can change the initial compression of the damping ring 30 by changing the depth of the mounting groove 102 on the bushing body 10, or by changing the hardness of the damping ring 30, thereby adjusting the support stiffness and thus adjusting the critical speed of the rotor. The damping ring 30 can also be centered, and there is no need to add additional squirrel cage elastic support, which simplifies the structure and reduces the weight.

[0055] Furthermore, the damping ring 30 may be an O-ring.

[0056] Furthermore, the damping ring 30 may be made of a rubber material such as fluororubber, nitrile rubber, polyurethane rubber, silicone rubber, etc., so as to dissipate the vibration energy through the viscoelastic damping of the rubber material.

[0057] Preferably, the damping ring 30 is made of fluororubber, which is more resistant to high temperatures and corrosion, thereby avoiding the influence of the damping ring 30 caused by the engine working in a high temperature environment.

[0058] In some embodiments, see Figure 3 As shown, a transition portion 104 is formed between the boss portion 101 and the inner peripheral wall of the bushing body 10 by chamfering, and the transition portion 104 is suitable for smoothly abutting against the damping ring 30, thereby preventing the damping ring 30 from stress concentration during the extrusion process and avoiding damage to the damping ring 30.

[0059] In some embodiments, see Figure 4As shown, the mounting groove 102 is a dovetail groove structure; the boss portion 101 forms a convex angle 105 on the side close to the damping ring 30 along the axial direction, and the convex angle 105 is set at an acute angle with the inner peripheral wall of the bushing body 10, and the convex angle 105 is suitable for limiting the damping ring 30.

[0060] In this embodiment, the mounting groove 102 adopts a dovetail groove structure. On the one hand, the convex corner 105 of the dovetail groove structure can be used to clamp the damping ring 30, thereby facilitating the installation of the damping ring 30. On the other hand, the convex corner 105 is set at an acute angle to the inner peripheral wall of the bushing body 10, which can make the wall surface of the mounting groove 102 shrink outward to form a conical wall surface. When the damping ring 30 is compressed and deformed, the outwardly contracted wall surface will provide a constraint, thereby increasing the friction damping between the damping ring 30 and the conical wall surface.

[0061] In some embodiments, the damping ring 30 is interference fit with the outer ring of the bearing body 20 .

[0062] In this embodiment, in order to prevent the damping ring 30 from loosening, the inner diameter of the damping ring 30 can be made slightly smaller than the outer diameter of the bearing body 20 so that the damping ring 30 is interference-fitted on the outer ring of the bearing body 20, which is beneficial to improving the fatigue performance of the damping ring 30.

[0063] In some embodiments, the number of the damping rings 30 is at least two, so as to ensure the stability of the engine rotor system.

[0064] In some embodiments, see Figure 5 As shown, the bushing body 10 includes a first bushing 11 , and at least two mounting grooves 102 are arranged on one side of the first bushing 11 radially facing the bearing body 20 . The mounting grooves 102 are arranged on the bushing body 10 at intervals along the axial direction, and a damping ring 30 is arranged in each mounting groove 102 .

[0065] In this embodiment, the length of the bushing is extended axially to form Figure 5 The first bushing 11 shown is provided with additional mounting grooves 102 to accommodate more damping rings 30 , thereby ensuring the stability of the engine rotor system.

[0066] It should be noted that the number of the mounting grooves 102 on the first bushing 11 can be two, or three, four, or five, etc. It can be adjusted according to the actual engine damping requirements and is not limited to the situation described in this embodiment.

[0067] In some embodiments, see Figure 6As shown, the bushing body 10 includes a second bushing 12 and a third bushing 13, and the third bushing 13 is arranged between the second bushing 12 and the outer ring of the bearing body 20; the third bushing 13 is provided with at least one mounting groove 102 along the radial side facing the bearing body 20, and the second bushing 12 is provided with at least one mounting groove 102 along the radial side facing the third bushing 13, and a damping ring 30 is arranged in each mounting groove 102, so that an extrusion gap 103 is formed between the outer ring of the bearing body 20 and the inner circumferential wall of the third bushing 13 and between the outer circumferential wall of the third bushing 13 and the inner circumferential wall of the second bushing 12 along the radial interval.

[0068] In this embodiment, if the axial size of the bushing is limited, the number of bushings can be increased in the radial direction to form Figure 6 The second bushing 12 and the third bushing 13 are shown, and mounting grooves 102 are provided on the additional bushings to accommodate more damping rings 30, thereby ensuring the stability of the engine rotor system.

[0069] It should be noted that the number of radially increased bushings can be two, three, four or five..., and the number of mounting grooves 102 on each bushing can be one or more, which can be adjusted according to the actual engine damping requirements and is not limited to the situation described in this embodiment.

[0070] According to an embodiment of the present invention, on the other hand, a working method of the damping structure as described above is also provided, comprising:

[0071] By changing the depth of the mounting groove 102, the initial compression rate of the damping ring 30 is changed to adjust the support stiffness of the damping ring 30, thereby adjusting the critical speed of the rotor system;

[0072] and / or, by changing the hardness of the damping ring 30 to adjust the support stiffness of the damping ring 30, thereby adjusting the critical speed of the rotor system;

[0073] Centering and support are performed by means of a damping ring 30;

[0074] The energy of the vibration is dissipated by the viscoelastic damping of the damping ring 30 .

[0075] It should be noted that, according to the performance requirements of the engine, after meeting the margin requirements of the engine critical speed design, changing the support stiffness is the main means of adjusting the critical speed. Generally, the greater the support stiffness, the greater the critical speed. Compared with adjusting the critical speed by increasing or decreasing the stiffness of the squirrel cage elastic support, the working method of the damping structure of the present invention changes the initial compression rate of the damping ring 30 by changing the depth of the mounting groove 102, thereby changing the range of the support stiffness of the damping ring 30, and then adjusting the critical speed of the rotor system. No additional squirrel cage elastic support is required, which is conducive to simplifying the structure and reducing weight.

[0076] The following simulation calculation is performed on the stiffness of the damping ring 30 to verify that the depth of the mounting groove 102 can adjust the critical speed of the damping structure of the present invention. Taking the damping structure of two damping rings 30 as an example, the structural parameters are shown in Table 1 below.

[0077] Table 1 Damping structure dimensions (unit: mm)

[0078]

[0079] In the simulation, the bushing body 10 is fixed, and the bearing body 20 gradually squeezes the damping ring by 0.1 mm. The stiffness of the damping ring is obtained. In the formula, ΔX is the displacement difference of the damping ring, and ΔF is the reaction force difference of the damping ring. The stiffness values ​​of the damping ring under different depths of the installation groove 102 are obtained by simulation, as shown in Table 2 below.

[0080] Table 2 Stiffness of the damping ring at different initial compression rates

[0081] Groove depth (mm) 1.4 1.45 1.5 1.55 1.6 Initial compression ratio 16.1％ 13.3％ 10.6％ 8.3％ 5％ Static stiffness(N / m) 1.89e6 1.61e6 1.37e6 1.2e6 0.78e6

[0082] The results show that as the depth of the mounting groove 102 decreases, that is, the initial compression rate of the damping ring 30 increases, the stiffness of the damping ring 30 also increases. Changing the depth of the mounting groove 102 can adjust the stiffness of the damping ring 30 .

[0083] Therefore, before manufacturing the damping structure of the present invention, simulation results of simulation software such as Ansys can be used to provide a basis for the design of the damping structure of the present invention, optimize the damping structure parameters, and adjust the critical speed of the rotor system.

[0084] Regarding the selection of damping structure materials, the engine works in a high temperature environment, and the temperature should be avoided as much as possible to affect the damping structure. The material of the damping ring 30 is a rubber material, and common rubber materials include fluororubber, nitrile rubber, polyurethane rubber, silicone rubber, etc. Among them, fluororubber is more resistant to high temperature and corrosion. Therefore, in this embodiment, the material of the damping ring 30 is selected from fluororubber.

[0085] For the selection of the hardness value of the damping ring 30, the following takes the fluororubber with a hardness range of 65A to 85A as an example, using the relationship between the hardness Hr and the elastic modulus E: lgE = 0.0198H r -0.5432, the elastic modulus of the damping ring 30 is obtained, and simulation calculation is carried out. The results are as follows Figure 7 shown.

[0086] The results show that when the initial compression rate is 16.1%, the stiffness increases by 2.24e6 N / m; when the initial compression rate is 13.3%, the stiffness increases by 1.91e6 N / m; when the initial compression rate is 10.6%, the stiffness increases by 1.63e6 N / m. This indicates that the greater the initial compression rate, the greater the influence of the stiffness of the damping ring 30 on the hardness of the rubber material.

[0087] A large change in the support stiffness will cause instability in the rotor system. Therefore, the critical speed cannot be adjusted solely by the compression rate of the damping ring 30. The initial compression rate of the damping ring 30 should not be too large. After determining the initial compression rate, a damping ring 30 of appropriate hardness can be selected, thereby adjusting the stiffness value of the damping ring 30 to meet the actual engine vibration reduction requirements.

[0088] The working method of the damping structure provided by the present invention changes the initial compression rate of the damping ring 30 by changing the depth of the installation groove 102, and / or, by changing the hardness of the damping ring 30, so as to adjust the support stiffness of the damping ring 30, thereby adjusting the critical speed of the rotor system, and no additional squirrel cage elastic support is required, which is conducive to simplifying the structure and reducing the weight; centering and support are performed by the damping ring 30, and there is no need to set up an oil supply device and an oil supply hole and an oil supply path such as an oil supply hole, and the weight of the damping ring 30 is lighter, which greatly reduces the weight of the structure and reduces the manufacturing cost, which is conducive to improving the thrust-to-weight ratio of the engine, and is more suitable for the elastic support of the rotor system of a short-life, low-cost engine. Bearing design; the vibratory energy is dissipated by the viscoelastic damping of the damping ring 30. When the rotor is vibrated by the unbalanced force during high-speed rotation, the vibration load is transmitted to the outer ring of the bearing body 20 through the shaft neck. The outer ring of the bearing body 20 squeezes the damping ring 30 and does work on the damping ring 30. During the deformation process, the viscoelastic damping of the damping ring 30 is used to convert part of the vibration energy into internal energy consumption. When the rotor exceeds the critical speed, the unbalanced response of the rotor can be effectively suppressed, thereby improving the stability of the rotor system. Compared with the squeeze film damper, there will be no rubbing caused by the nonlinearity of the oil film force. Even if the rotor tapers, stable damping can be provided, and the vibration reduction effect and reliability are better.

[0089] In some embodiments, changing the hardness of the damping ring 30 includes:

[0090] According to the actual operating temperature of the engine, use the formula H rt =H rst +β(T-23), calculate the change of the hardness of the damping ring 30, so as to select the damping ring 30 with appropriate hardness, determine the appropriate support stiffness range of the damping ring 30, and adjust the critical speed of the rotor system, where H rt is the material hardness at ambient temperature T, H rst is the material hardness at standard room temperature, T is the ambient temperature, and β is the temperature correction coefficient.

[0091] Please note that, see Figure 8 As shown, in order to verify the vibration reduction characteristics of the damping structure of the present invention, a bidirectional excitation test can be used to test the dynamic characteristics of the damping ring 30 and the oil film under the action of dynamic load. The test equipment is as follows: Figure 8 As shown. During the test, the signal generator can generate two signals with the same frequency but a phase difference of 90°. The two power amplifiers drive the exciter to work. The exciter is connected to the squirrel cage through a flexible rod and an impedance head. The exciter applies two exciting forces FcosΩt and FsinΩt in two directions perpendicular to each other, which is equivalent to exciting the journal with a rotation force with an amplitude of F and a rotation frequency of Ω, thereby simulating the excitation of the damping structure by the unbalanced force of the rotor, and then simulating the working state of the damping structure in a non-rotating state. The impedance head records the excitation and response signals, and obtains the dynamic characteristics of the damping ring based on the mechanical impedance method.

[0092] The verification results show that during high-speed rotation of the rotor, the vibration load is transmitted to the damping ring 30 and the bushing body 10 through the fulcrum bearing, and the extrusion deformation of the damping ring 30 is used to consume energy, thereby reducing the outward vibration of the bushing body 10.

[0093] According to an embodiment of the present invention, on another aspect, an engine rotor system is provided, comprising: a rotor body, and the damping structure as described above.

[0094] The engine rotor system in this embodiment includes the above-mentioned damping structure. Therefore, the engine rotor system in this embodiment includes all the beneficial effects of the above-mentioned damping structure.

[0095] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A damping structure, characterized in that: include: A bushing body (10) is sleeved on the outer ring of the bearing body (20); A plurality of bosses (101) are provided on one side of the bushing body (10) radially facing the bearing body (20), and a mounting groove (102) is formed between two adjacent bosses (101) at intervals along the axial direction; The damping ring (30) is installed in the installation groove (102), and the boss portion (101) is suitable for limiting the axial displacement of the damping ring (30); the damping ring (30) is made of viscoelastic material, and the damping ring (30) elastically abuts against the outer ring of the bearing body (20) along the radial direction toward the side of the bearing body (20), and an extrusion gap (103) is formed between the outer ring of the bearing body (20) and the inner peripheral wall of the bushing body (10) along the radial interval.

2. The damping structure according to claim 1, characterized in that: A transition portion (104) is formed between the boss portion (101) and the inner peripheral wall of the bushing body (10) by chamfering, and the transition portion (104) is suitable for smoothly abutting against the damping ring (30).

3. The damping structure according to claim 1, characterized in that: The mounting groove (102) is a dovetail groove structure; the boss portion (101) forms a convex angle (105) on the side axially close to the damping ring (30), and the convex angle (105) is set at an acute angle with the inner peripheral wall of the bushing body (10), and the convex angle (105) is suitable for limiting the damping ring (30).

4. The damping structure according to claim 1, characterized in that: The damping ring (30) is interference fit with the outer ring of the bearing body (20).

5. The damping structure according to any one of claims 1 to 4, characterized in that: The number of the damping rings (30) is at least two.

6. The damping structure according to claim 5, characterized in that: The bushing body (10) comprises a first bushing (11), and at least two mounting grooves (102) are arranged on a side of the first bushing (11) radially facing the bearing body (20). The mounting grooves (102) are arranged on the bushing body (10) at intervals along the axial direction, and the damping ring (30) is arranged in each mounting groove (102).

7. The damping structure according to claim 5, characterized in that: The bushing body (10) comprises a second bushing (12) and a third bushing (13), wherein the third bushing (13) is arranged between the second bushing (12) and the outer ring of the bearing body (20); the third bushing (13) is provided with at least one mounting groove (102) along the radial direction toward the bearing body (20), and the second bushing (12) is provided with at least one mounting groove (102) along the radial direction toward the third bushing (13), and the damping ring (30) is arranged in each mounting groove (102).

8. A working method of the damping structure according to any one of claims 1 to 7, characterized in that: include: The initial compression rate of the damping ring (30) is changed by changing the depth of the installation groove (102) to adjust the support stiffness of the damping ring (30), thereby adjusting the critical speed of the rotor system; and / or, by changing the hardness of the damping ring (30) to adjust the support stiffness of the damping ring (30), thereby adjusting the critical speed of the rotor system; Centering and support are performed by means of a damping ring (30); The energy of the vibration is dissipated through the viscoelastic damping of the damping ring (30).

9. The working method of the damping structure according to claim 8, characterized in that: Changing the hardness of the damping ring (30) comprises: According to the actual operating temperature of the engine, use the formula H rt =H rst +β(T-23), calculate the change in the hardness of the damping ring (30), and thus select a damping ring (30) of appropriate hardness, where H rt is the material hardness at ambient temperature T, H rst is the material hardness at standard room temperature, T is the ambient temperature, and β is the temperature correction coefficient.

10. An engine rotor system, characterized in that: include: A rotor body, and a damping structure as claimed in any one of claims 1 to 7.

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