A method for evaluating the damping performance of an elastic ring type fulcrum vibration suppression device

Abstract

This invention provides a method for evaluating the vibration reduction performance of an elastic ring-type pivot vibration suppression device. The elastic ring-type pivot vibration suppression device includes a coaxial rigid outer ring, an elastic ring, and a bearing outer ring arranged from the outside in. The method includes: obtaining the oil film force F at the design speed; and calculating the oil film radial force F based on the oil film force F. r Oil film tangential force F t According to formula F r / F t The vibration reduction performance value Kc at the design speed is calculated and compared with the vibration reduction performance evaluation index to evaluate the vibration reduction performance of the elastic ring support vibration suppression device at the design speed. The evaluation method designed in this invention can effectively evaluate the vibration reduction effect of the elastic ring support vibration suppression device design at an earlier stage, and can be used to guide the design of the elastic ring support vibration suppression device.

Description

Technical Field

[0001] This invention belongs to the field of aero-engine design and relates to the testing technology of rotor system vibration suppression devices, specifically a method for evaluating the vibration reduction performance of an elastic ring-type support vibration suppression device. Background Technology

[0002] In the design process of aero-engines, the pursuit of high thrust-to-weight ratio and high reliability places engines in high-load and high-speed operating environments, leading to increasingly prominent engine vibration issues. Currently, to improve engine reliability and durability, vibration suppression devices are typically applied to the rotor system. For example, elastic ring-type pivot vibration suppression devices are used to isolate externally transmitted vibrations in aero-engine rotor systems. However, due to their complex structural parameters and application only in aero-engines, their design currently relies heavily on experience or trial-and-error methods. A theoretical approach is lacking to quantitatively characterize the vibration reduction effect of these devices. Often, their vibration reduction effect can only be discovered through externally transmitted vibration tests during the core engine or even the entire engine testing phase, severely impacting the aero-engine development cycle. Summary of the Invention

[0003] To address the lack of evaluation methods for the vibration reduction effect of elastic ring fulcrum vibration suppression devices, this invention designs a method for evaluating the vibration reduction performance of elastic ring fulcrum vibration suppression devices. This method can effectively evaluate the vibration reduction effect of the design of elastic ring fulcrum vibration suppression devices at an early stage of the design process, and can be used to guide the design of elastic ring fulcrum vibration suppression devices.

[0004] The technical solution to achieve the purpose of the invention is as follows: A method for evaluating the vibration reduction performance of an elastic ring type fulcrum vibration suppression device, wherein the elastic ring type fulcrum vibration suppression device includes a coaxial rigid outer ring, an elastic ring, and a bearing outer ring arranged from the outside to the inside, and includes the following steps:

[0005] Obtain the oil film force F at the design speed;

[0006] Calculate the radial force F of the oil film based on the oil film force F. r Oil film tangential force F t ;

[0007] According to formula F r / F t The vibration reduction performance value Kc at the design speed is calculated and compared with the vibration reduction performance evaluation index to evaluate the vibration reduction performance of the elastic ring support vibration suppression device at the design speed.

[0008] Furthermore, the method for obtaining the oil film force F at the design speed includes:

[0009] Based on simulation or test specimens, the oil film pressure P of the elastic ring type fulcrum vibration suppression device at the design speed is obtained. The oil film pressure P is the oil film pressure of the outer oil film formed by the elastic ring and the rigid outer ring.

[0010] Based on the oil film pressure P, the design parameters of the elastic ring fulcrum vibration suppression device, and the operating parameters at the design speed, the oil film force F is calculated.

[0011] Furthermore, the operating parameters at the design speed include the arc θ of the line connecting the oil film force vector with the center of the rigid outer ring and the center of the bearing outer ring, the area s of the inner surface of the rigid outer ring bearing the oil film pressure, and the offset distance d of the bearing outer ring relative to its working state at the design speed.

[0012] The design parameters of the elastic ring type fulcrum vibration suppression device include the axial length l of the elastic ring type fulcrum vibration suppression device and the inner radius R of the rigid outer ring;

[0013] The formula for calculating the oil film force F is:

[0014] F(θ)=P(θ)×d(s), d(s)=l·R·d(θ).

[0015] Furthermore, the radial force F of the oil film r The calculation formula is:

[0016]

[0017] Oil film tangential force F t The calculation formula is:

[0018]

[0019] Furthermore, the vibration reduction performance evaluation index ranges from 0 to 1.

[0020] Furthermore, the vibration reduction performance of the elastic ring-type pivot vibration suppression device at the design speed was evaluated, including the following results:

[0021] When Kc is greater than zero and less than 1, the vibration reduction performance of the elastic ring fulcrum vibration suppression device meets the standard at the set rotation speed.

[0022] When Kc is greater than or equal to 1, the vibration reduction performance of the elastic ring fulcrum vibration suppression device is not up to standard at the set rotation speed, and the elastic ring fulcrum vibration suppression device needs to be optimized.

[0023] Preferred optimization methods for elastic ring-type fulcrum vibration suppression devices include:

[0024] Adjust the height or number of bosses on the inner boss of the elastic ring;

[0025] Alternatively, adjust the height or number of protrusions on the outer protrusion of the elastic ring.

[0026] Compared with the prior art, the beneficial effects of the present invention are: the vibration reduction performance evaluation method of the elastic ring fulcrum vibration suppression device designed in this invention links oil film damping with oil film stiffness, using the ratio of their effects (oil film damping can be expressed as F...). t / (d×Ω), the oil film stiffness can be obtained through F r The physical characterization of the magnitude of (where Ω is the design speed and d is the offset distance) is used to evaluate the design effectiveness of the elastic ring support vibration suppression device. This method is applicable to the rotor support design stage. By combining oil film pressure simulation technology and experimental specimen testing, various operating parameters can be obtained for evaluation, effectively shortening the R&D cycle and reducing verification costs.

[0027] Experiments have verified that the elastic ring pivot vibration suppression device designed using the method of this invention reduces the root mean square value of the fundamental frequency of the casing vibration acceleration of a high-speed, low-thrust engine without high-speed dynamic balancing or internal dynamic balancing. (root mean square value of velocity) Furthermore, the maximum external vibration of large and medium-sized thrust engines does not exceed 3g, and the external vibration of the core engine does not exceed 2g. Attached Figure Description

[0028] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are merely for the purpose of more clearly illustrating the technical solutions in the embodiments of the present invention or the prior art. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0029] Figure 1 This is a schematic diagram of the elastic ring fulcrum vibration suppression device in a specific implementation embodiment;

[0030] Figure 2 This is a flowchart of the vibration reduction performance evaluation method for the elastic ring fulcrum vibration suppression device of the present invention;

[0031] Figure 3 This is a schematic diagram illustrating the principle of the vibration reduction performance evaluation method for the elastic ring-type fulcrum vibration suppression device in a specific implementation.

[0032] Figure 4 This is a schematic diagram of a vibration suppression device for an elastic ring fulcrum at a specific rotational speed, as designed in a specific implementation method.

[0033] Among them, 1. rigid outer ring; 2. elastic ring; 3. bearing outer ring; 4. outer oil film. Detailed Implementation

[0034] The present invention will be further described below with reference to specific embodiments, and the advantages and features of the present invention will become clearer as a result. However, these embodiments are merely exemplary and do not constitute any limitation on the scope of the present invention. Those skilled in the art should understand that modifications or substitutions can be made to the details and form of the technical solutions of the present invention without departing from the spirit and scope of the present invention, but all such modifications and substitutions fall within the protection scope of the present invention.

[0035] In the description of this embodiment, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the invention.

[0036] Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0037] This specific embodiment provides a method for evaluating the vibration reduction performance of an elastic ring-type fulcrum vibration suppression device. (See also...) Figure 1 As shown, the elastic ring type fulcrum vibration suppression device includes a coaxial rigid outer ring 1, an elastic ring 2, and a bearing outer ring 3 arranged from the outside in.

[0038] For the evaluation method of vibration reduction performance of elastic ring-type pivot vibration suppression devices, please refer to [link / reference]. Figure 2 and Figure 3 As shown, it includes the following steps:

[0039] S1. Obtain the oil film force F at the design speed;

[0040] s2. Calculate the radial force F of the oil film based on the oil film force F. r Oil film tangential force F t ;

[0041] s3, according to formula F r / F t The vibration reduction performance value Kc at the design speed is calculated and compared with the vibration reduction performance evaluation index to evaluate the vibration reduction performance of the elastic ring support vibration suppression device at the design speed.

[0042] In one embodiment, step S1, the method for obtaining the oil film force F at the design rotational speed, includes:

[0043] S101. Based on simulation or test specimen, obtain the oil film pressure P of the elastic ring type fulcrum vibration suppression device at the design speed. The oil film pressure P is the oil film pressure of the outer oil film 4 formed by the elastic ring and the rigid outer ring.

[0044] S102. Calculate the oil film force F based on the oil film pressure P, the design parameters of the elastic ring fulcrum vibration suppression device, and the working parameters at the design speed.

[0045] See Figure 4 As shown, the operating parameters at the design speed include the arc θ of the line connecting the oil film force vector with the center of the rigid outer ring and the center of the bearing outer ring, the area s of the inner hole surface of the rigid outer ring bearing the oil film pressure, and the offset distance d of the bearing outer ring relative to its working state at the design speed.

[0046] See Figure 4 As shown, the design parameters of the elastic ring type fulcrum vibration suppression device include the axial length l of the elastic ring type fulcrum vibration suppression device and the inner radius R of the rigid outer ring;

[0047] The formulas for calculating S103 and oil film force F are:

[0048] F(θ)=P(θ)×d(s), d(s)=l·R·d(θ).

[0049] In one embodiment, in step s2, the oil film radial force F is calculated using the oil film force F. r Oil film tangential force F t The method is as follows:

[0050] Among them, the radial force F of the oil film r The calculation formula is:

[0051]

[0052] Among them, the tangential force F of the oil film t The calculation formula is:

[0053]

[0054] In one embodiment, in step S4, the vibration reduction performance evaluation index ranges from 0 to 1.

[0055] Furthermore, by calculating the vibration reduction performance value Kc at the design speed through the above steps, and comparing it with the vibration reduction performance evaluation index range of 0 to 1, the evaluation result of meeting the standard or failing to meet the standard is obtained.

[0056] Specifically, when Kc is greater than zero and less than 1, the vibration reduction performance of the elastic ring fulcrum vibration suppression device meets the standard at the set rotation speed.

[0057] When Kc is greater than or equal to 1, the vibration reduction performance of the elastic ring fulcrum vibration suppression device is not up to standard at the set rotation speed, and the elastic ring fulcrum vibration suppression device needs to be optimized.

[0058] In an optional embodiment, the optimization method for the elastic ring type fulcrum vibration suppression device includes: adjusting the height or number of inner bosses on the elastic ring, or adjusting the height or number of outer bosses on the elastic ring; other methods capable of adjusting Kc can also be used for adjustment. In this specific embodiment, after optimization using multiple schemes, the method with the smallest Kc value in the range of 0 to 1 is selected as the optimal method for the elastic ring type fulcrum vibration suppression device.

[0059] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

[0060] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A method for evaluating the vibration reduction performance of an elastic ring-type fulcrum vibration suppression device, the elastic ring-type fulcrum vibration suppression device comprising a coaxial rigid outer ring, an elastic ring, and a bearing outer ring arranged from the outside in, characterized in that... Includes the following steps: Obtain the oil film force F at the design speed; Calculate the radial force of the oil film based on the oil film force F. Oil film tangential force ; According to the formula / The vibration reduction performance value Kc at the design speed is calculated and compared with the vibration reduction performance evaluation index to evaluate the vibration reduction performance of the elastic ring support vibration suppression device at the design speed. The method for obtaining the oil film force F at the design speed includes: Based on simulation or test specimens, the oil film pressure P of the elastic ring type fulcrum vibration suppression device at the design speed is obtained. The oil film pressure P is the oil film pressure of the outer oil film formed by the elastic ring and the rigid outer ring. Based on the oil film pressure P, the design parameters of the elastic ring type fulcrum vibration suppression device, and the operating parameters at the design speed, the oil film force F is calculated. The operating parameters at the design speed include the arc θ of the line connecting the oil film force vector to the center of the rigid outer ring and the center of the bearing outer ring, the area s of the inner surface of the rigid outer ring bearing the oil film pressure, and the offset distance d of the bearing outer ring relative to its initial operating position at the design speed. The design parameters of the elastic ring type fulcrum vibration suppression device include the axial length of the device. The inner radius R of the rigid outer ring; The formula for calculating the oil film force F is: ， ； Oil film radial force The calculation formula is: ； Oil film tangential force The calculation formula is: 。 2. The method for evaluating the vibration reduction performance of the elastic ring-type fulcrum vibration suppression device according to claim 1, characterized in that: The vibration reduction performance evaluation index ranges from 0 to 1.

3. The method for evaluating the vibration reduction performance of the elastic ring-type fulcrum vibration suppression device according to claim 2, characterized in that: The evaluation results of the vibration reduction performance of the elastic ring-type pivot vibration suppression device at the design speed include: When Kc is greater than zero and less than 1, the vibration reduction performance of the elastic ring fulcrum vibration suppression device meets the standard at the set rotation speed. When Kc is greater than or equal to 1, the vibration reduction performance of the elastic ring fulcrum vibration suppression device is not up to standard at the set rotation speed, and the elastic ring fulcrum vibration suppression device needs to be optimized.

4. The method for evaluating the vibration reduction performance of the elastic ring-type fulcrum vibration suppression device according to claim 3, characterized in that: An optimization method for an elastic ring-type fulcrum vibration suppression device includes: Adjust the height or number of bosses on the inner boss of the elastic ring; Alternatively, adjust the height or number of protrusions on the outer protrusion of the elastic ring.

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