CN119885713A - Design method of hydraulic rubber composite vibration isolation device - Google Patents
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Abstract
本发明公开了一种液压橡胶复合减振装置的设计方法，属于航空设备隔振安装技术领域，用于液压橡胶复合隔振装置的设计，能缩短隔振装置的设计时间，并提高研发试验的安全性。本方法包括：步骤S1，根据发动机在不同频率下刚度和阻尼的要求，进行参数匹配理论计算、仿真和设计，得到减振装置的目标参数，包括静刚度、及在不同频率下的动刚度和阻尼系数；步骤S2，搭建减振装置的集中参数仿真模型，调整减振装置的关键参数，满足步骤S1的目标参数，关键参数包括减振装置的等效活塞面积、体积刚度、流道阻尼系数和惯性系数；步骤S3，对减振装置的静刚度、等效活塞面积、体积刚度和流道参数进行设计，形成设计方案，满足步骤S2的关键参数。
The present invention discloses a design method of a hydraulic rubber composite vibration isolation device, which belongs to the technical field of vibration isolation installation of aviation equipment, and is used for the design of a hydraulic rubber composite vibration isolation device, which can shorten the design time of the vibration isolation device and improve the safety of research and development tests. The method comprises: step S1, according to the requirements of stiffness and damping of the engine at different frequencies, parameter matching theoretical calculation, simulation and design are performed to obtain the target parameters of the vibration isolation device, including static stiffness, and dynamic stiffness and damping coefficient at different frequencies; step S2, building a concentrated parameter simulation model of the vibration isolation device, adjusting the key parameters of the vibration isolation device to meet the target parameters of step S1, and the key parameters include the equivalent piston area, volume stiffness, flow channel damping coefficient and inertia coefficient of the vibration isolation device; step S3, designing the static stiffness, equivalent piston area, volume stiffness and flow channel parameters of the vibration isolation device to form a design scheme to meet the key parameters of step S2.
Description
Technical Field
The invention belongs to the technical field of vibration isolation and installation of aviation equipment, and particularly relates to a design method of a hydraulic rubber composite vibration isolation device.
Background
The vibration isolation system of the aircraft engine mainly adopts a hydraulic rubber composite vibration isolation device for vibration isolation. Because the aircraft engine needs to transmit larger thrust and torque to the aircraft, the adopted hydraulic rubber composite vibration isolation device has higher requirements. If the connection stiffness between the engine and the vibration isolation system is high, the vibration of the engine is mostly transmitted to the aircraft body directly, and especially when the aircraft lands, the amplification factor of the impact acceleration of the engine during landing is required to be as small as possible. Therefore, the hydraulic rubber composite vibration isolation device is required to have lower rigidity and larger damping under specific impact frequency when an airplane lands, and the dynamic rigidity is rapidly increased after the dynamic rigidity is at the valley frequency and is stable after the dynamic rigidity reaches the peak value.
However, technical requirements of vibration reduction and impact resistance of engines of different types of aircrafts are different and are determined by the structure of the aircrafts and the type of the engines, so that hydraulic rubber composite vibration isolation devices adopted by the aircrafts of new types are required to be redesigned, so that performance parameters of the hydraulic rubber composite vibration isolation devices accord with the requirements of the aircrafts of new types, a great deal of time is consumed, a great deal of landing tests are carried out, and safety in the landing test process cannot be guaranteed.
Therefore, a design method of the hydraulic rubber composite vibration isolation device is needed, and the hydraulic rubber composite vibration isolation device can be rapidly and pertinently designed according to the technical requirements of engine vibration reduction and impact resistance of different types of aircrafts, so that the design time of the hydraulic rubber composite vibration isolation device is shortened, and the safety of research and development tests is improved.
Disclosure of Invention
The invention provides a design of a hydraulic rubber composite vibration isolation device, which is used for the design of the hydraulic rubber composite vibration isolation device, so that whether the hydraulic rubber composite vibration isolation device meets specific impact frequency and vibration isolation requirements during landing of a novel aircraft or not can be met, the design time of the hydraulic rubber composite vibration isolation device is shortened, and the safety of an aircraft research and development test is improved.
In order to achieve the above purpose, a design method of the hydraulic rubber composite vibration isolation device comprises the following steps:
Step S1, carrying out parameter matching theoretical calculation, simulation and design according to technical requirements of rigidity and damping of a target engine under different frequencies to obtain target parameters of the hydraulic rubber composite vibration damper, wherein the target parameters comprise static rigidity and dynamic rigidity and damping coefficients under different frequencies;
S2, determining and building a centralized parameter simulation model of the hydraulic rubber composite vibration damping device based on the basic structure of the hydraulic rubber composite vibration damping device, and adjusting key parameters of the hydraulic rubber composite vibration damping device to enable the key parameters to meet the target parameters obtained in the step S1, wherein the key parameters comprise equivalent piston area, volume rigidity, flow passage damping coefficient and inertia coefficient of the hydraulic rubber composite vibration damping device;
And S3, designing static rigidity, equivalent piston area, volume rigidity and runner parameters of the hydraulic rubber composite vibration damper to form a preliminary design scheme of the hydraulic rubber composite vibration damper so as to enable the hydraulic rubber composite vibration damper to meet the key parameters obtained in the step S2.
As shown in figure 1, the dynamic stiffness of the hydraulic rubber composite vibration isolation device gradually decreases in a low frequency band along with the increase of the frequency, rapidly increases to a peak value after reaching a valley value, and then tends to be stable along with the increase of the frequency, and the loss factor, namely the loss angle, of the vibration isolation device gradually increases along with the increase of the frequency at the beginning, rapidly decreases after reaching the peak value and is stable at a smaller value. In the technical requirements of rigidity and damping of engine installation, the dynamic rigidity of the hydraulic rubber composite vibration isolation device is required to be reduced in a certain small frequency range and is smaller than the static rigidity, and meanwhile, the hydraulic rubber composite vibration isolation device has a larger damping coefficient. The traditional design method is carried out by trial production and test methods, long-term and large-scale adjustment and test are needed to be carried out on the hydraulic rubber composite vibration isolation device for aiming at vibration isolation performance required by a target engine, and the design period is long after the optimization of multi-wheel structure versions. According to the design method, key parameters such as the equivalent piston area, the volume rigidity, the flow channel diameter and the length of the liquid rubber are adjusted by constructing a centralized parameter simulation model of the hydraulic rubber composite vibration isolation device, then the liquid rubber composite vibration isolation device is subjected to structural design to achieve the required vibration isolation performance, an actual product does not need to be manufactured in a trial mode before design shaping, and a structural shaping scheme is finally determined through checking and optimization of a plurality of rounds of virtual models. Because the virtual model simulation check and the optimized version period are far lower than those of trial production and test check, the design period and the cost can be greatly shortened.
Preferably, in the step S2, the hydraulic rubber composite vibration isolation device based on which the hydraulic rubber composite vibration isolation device centralized parameter simulation model is built comprises an upper body and a lower body, wherein the upper body is connected with the lower body through a runner plate, the upper body and the lower body are symmetrically arranged at the upper end and the lower end of the runner plate and respectively encircle a first hydraulic cavity and a second hydraulic cavity with the runner plate, the first hydraulic cavity is communicated with the second hydraulic cavity through a runner arranged on the runner plate, the upper body and the lower body both comprise a hydraulic cavity sleeve and a rubber spring, and a connecting mandrel which can be connected with a vibration isolation mounting device on an aircraft engine is embedded at the outer end of the rubber spring. The design period can be greatly shortened by adopting a standard mechanism model.
Preferably, in the step S2, when the key parameters of the hydraulic rubber composite vibration reduction device are adjusted, the adaptation is performed according to 1.6 to 2.4 times of the static stiffness in the target parameters obtained in the step S1. The hydraulic cavity is designed to reduce the static rigidity of the hydraulic rubber composite vibration damper, so that the static rigidity of the vibration damper after the design is designed to be 1.6-2.4 times of the technical requirement value is ensured to meet the technical requirement.
Preferably, in step S2, the key parameters of the hydraulic rubber composite vibration isolation device are adjusted according to the following formula, so that the dynamic stiffness of the hydraulic rubber composite vibration isolation device with respect to the vibration frequency SAnd damping coefficientThe target parameters obtained in the step S1 are satisfied:
Wherein, Is the combined rigidity of the two rubber springs (2),In order to be a damping coefficient,Is the equivalent piston area of the flow passage plate (5),、And the volume rigidity of the first hydraulic cavity (4) and the second hydraulic cavity (6) respectively,AndThe flow channel damping coefficient and the inertia coefficient are respectively,Is the average pressure at the time of static balance,For the initial displacement to be a function of the initial displacement,It can be obtained by means of a simulation calculation,、、、、、、AndThe values of (2) may be set directly.
Preferably, in step S3, the static stiffness is adjusted by adjusting the material of the rubber spring, increasing or decreasing the thickness of the rubber layer, and changing the structure of the separator.
Preferably, in step S3, the adjustment of the equivalent piston area is achieved by increasing the volume of the hydraulic chamber.
Preferably, in step S3, the adjustment of the volume stiffness is achieved by an adjustment of the shape and structure of the hydraulic chamber.
The rubber body structure is hollowed to design a hydraulic chamber, and the orthographic projection area of the hydraulic chamber is slightly larger than the equivalent piston area so as to ensure that the primary design value is close to the target value. And then carrying out finite element simulation on the primary structure, and calculating the static stiffness, equivalent piston area and volume stiffness of the primary structure. The hydraulic pressure adjusting device can realize static stiffness adjustment by adjusting structures such as increasing and decreasing rubber layer thickness and partition plates, realize projection area increase and decrease by increasing the volume of a hydraulic pressure cavity, thereby realizing equivalent piston area adjustment, and realize volume stiffness adjustment by adjusting the shape, structure and the like of the hydraulic pressure cavity. The three parameters have the characteristics of mutual influence, and multiple rounds of adjustment, checking and optimization are needed in adjustment, so that the accurate design is finally realized.
Preferably, in step S3, the channel is configured with a structure such as a flow channel pipe or a flow channel groove in the flow channel plate, and is precisely designed according to the matched diameter and length, so as to realize adjustment of the flow channel damping coefficient and the inertia coefficient.
Preferably, the design method further comprises a step S4 of accurately simulating the fluid-solid coupling dynamic performance of the primary design scheme obtained in the step S3, calculating the change rule of dynamic stiffness and damping values of the structural scheme under different frequencies and amplitudes, and carrying out local structure adjustment optimization according to simulation results to meet the technical requirements of a target engine and obtain the final design scheme of the hydraulic rubber composite vibration damper.
Preferably, the design method further comprises a step S5 of carrying out sample trial manufacture and static and dynamic stiffness test check on the final design scheme formed in the step S4, verifying the dynamic and static properties of the sample, and then installing the liquid rubber vibration damper into a vibration damper system for vibration isolation and drop test verification.
The present invention will be described in detail with reference to examples.
Drawings
The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain the application. In the drawings:
FIG. 1 is a graph showing the dynamic stiffness and loss angle of a hydraulic rubber composite vibration isolation device as a function of frequency;
fig. 2 is a schematic flow chart of a design method of a hydraulic rubber composite vibration isolation device according to an embodiment of the invention;
fig. 3 is an external view schematically showing a hydraulic rubber composite vibration isolation device according to an embodiment of the present invention;
Fig. 4 is a schematic view showing an inclined appearance of a hydraulic rubber composite vibration isolation device according to an embodiment of the present invention;
Fig. 5 is a perspective cross-sectional view of a hydraulic rubber composite vibration isolation device according to an embodiment of the present invention;
Fig. 6 is a vertical and symmetrical sectional view of a hydraulic rubber composite vibration isolation device according to an embodiment of the present invention.
Wherein the above figures include the following reference numerals:
1. the hydraulic device comprises a hydraulic cavity sleeve, a rubber spring, a connecting mandrel, a first hydraulic cavity, a runner plate, a runner and a second hydraulic cavity, wherein the connecting mandrel is arranged in the hydraulic cavity sleeve, the rubber spring is arranged in the hydraulic cavity sleeve, and the connecting mandrel is arranged in the hydraulic cavity sleeve.
Detailed Description
Embodiments of the invention are described in detail below with reference to the attached drawings, but the invention can be implemented in a number of different ways, which are defined and covered by the claims.
Referring to fig. 1, in a preferred embodiment of the present invention, there is provided a design method including the steps of:
Step S1, carrying out parameter matching theoretical calculation, simulation and design according to technical requirements of rigidity and damping of a target engine under different frequencies to obtain target parameters of the hydraulic rubber composite vibration damper, wherein the target parameters comprise static rigidity and dynamic rigidity and damping coefficients under different frequencies;
Step S2, see figures 3-6, comprising an upper body and a lower body, wherein the upper body is connected with the lower body through a runner plate (5), the upper body and the lower body are symmetrically arranged at the upper end and the lower end of the runner plate (5) and respectively enclose a first hydraulic cavity (4) and a second hydraulic cavity (6) with the runner plate (5), the first hydraulic cavity (4) is communicated with the second hydraulic cavity (6) through a runner (51) arranged on the runner plate (5), the upper body and the lower body both comprise a hydraulic cavity sleeve (1) and a rubber spring (2), and a connecting mandrel (3) which can be connected with a vibration isolation mounting device on an aircraft engine is embedded at the outer end of the rubber spring (2);
setting up a centralized parameter simulation model of the hydraulic rubber composite vibration damper based on the basic mechanism of the hydraulic rubber composite vibration damper and based on the basic mechanism of the hydraulic rubber composite vibration damper, and adjusting key parameters of the hydraulic rubber composite vibration damper to enable the key parameters to meet the target parameters obtained in the step S1, wherein the key parameters comprise equivalent piston area, volume rigidity, flow passage damping coefficient and inertia coefficient of the hydraulic rubber composite vibration damper;
Wherein, when the key parameters of the liquid rubber composite vibration damper are adjusted, the key parameters of the hydraulic rubber composite vibration damper are adjusted according to the following formula, and the dynamic stiffness of the hydraulic rubber composite vibration damper about the vibration frequency S is adjusted according to 2 times of the static stiffness in the target parameters obtained in the step S1 And damping coefficientThe target parameters obtained in the step S1 are satisfied:
Wherein, Is the combined rigidity of the two rubber springs (2),In order to be a damping coefficient,Is the equivalent piston area of the flow passage plate (5),、And the volume rigidity of the first hydraulic cavity (4) and the second hydraulic cavity (6) respectively,AndThe flow channel damping coefficient and the inertia coefficient are respectively,Is the average pressure at the time of static balance,For the initial displacement to be a function of the initial displacement,It can be obtained by means of a simulation calculation,、、、、、、AndThe values of (2) may be set directly.
Step S3, designing static rigidity, equivalent piston area, volume rigidity and runner parameters of the hydraulic rubber composite vibration damper to form a preliminary design scheme of the hydraulic rubber composite vibration damper so as to enable the hydraulic rubber composite vibration damper to meet the key parameters obtained in the step S2;
The hydraulic rubber composite damping device comprises a hydraulic rubber composite damping device, a hydraulic cavity, a flow channel plate, a flow channel pipe, a flow channel groove, a flow channel damping coefficient and an inertia coefficient, wherein the material of the rubber spring (2) is adjusted, the thickness of the rubber layer is increased or decreased, the structure of the partition plate is changed, the combined rigidity is adjusted, the static rigidity of the hydraulic rubber composite damping device is adjusted, the volume of the hydraulic cavity is increased or compared, the equivalent piston area is adjusted, the volume rigidity is adjusted through the shape and the structure of the hydraulic cavity, the flow channel pipe, the flow channel groove and the like are designed in the flow channel plate, and the flow channel damping coefficient and the inertia coefficient are adjusted according to the matched diameter and length. When the three parameters are regulated, firstly static rigidity is regulated, then equivalent piston area is regulated, and finally volume rigidity is regulated.
And S4, carrying out fluid-solid coupling dynamic performance accurate simulation on the primary design scheme obtained in the step S3, calculating the change rule of dynamic stiffness and damping values of the structural scheme under different frequencies and amplitudes, and carrying out local structure adjustment and optimization according to simulation results so as to meet the technical requirements of a target engine and obtain the final design scheme of the hydraulic rubber composite vibration damper.
And S5, performing sample trial manufacture and static and dynamic stiffness test check on the final structural scheme formed in the step S4, verifying the dynamic and static properties of the sample, and then installing the liquid rubber vibration damper into a vibration damper system for vibration isolation and drop test verification.
So far, the design of the hydraulic rubber composite vibration damper is completed.
The foregoing describes in detail preferred embodiments of the present invention. It should be understood that numerous modifications and variations can be made in accordance with the concepts of the invention by one of ordinary skill in the art without undue burden. Therefore, all technical solutions which can be obtained by logic analysis, reasoning or limited experiments based on the prior art by the person skilled in the art according to the inventive concept shall be within the scope of protection defined by the claims.
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| CN202411788302.XA CN119885713B (en) | 2024-12-06 | Design method of a hydraulic rubber composite vibration isolation device |
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| CN202411788302.XA CN119885713B (en) | 2024-12-06 | Design method of a hydraulic rubber composite vibration isolation device |
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Citations (4)
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| CN106407573A (en) * | 2016-09-23 | 2017-02-15 | 河海大学常州校区 | A Pareto-based hydraulically damped rubber mount structure parameter multi-objective optimization method |
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| US20220065326A1 (en) * | 2019-09-06 | 2022-03-03 | Zhuzhou Times New Material Technology Co., Ltd | Liquid composite spring and method for adjusting stiffness and damping property thereof |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN106407573A (en) * | 2016-09-23 | 2017-02-15 | 河海大学常州校区 | A Pareto-based hydraulically damped rubber mount structure parameter multi-objective optimization method |
| US20220065326A1 (en) * | 2019-09-06 | 2022-03-03 | Zhuzhou Times New Material Technology Co., Ltd | Liquid composite spring and method for adjusting stiffness and damping property thereof |
| CN113505488A (en) * | 2021-07-19 | 2021-10-15 | 东风汽车集团股份有限公司 | NVH target determination method for suspension damping rubber |
| CN118008990A (en) * | 2024-03-14 | 2024-05-10 | 株洲时代新材料科技股份有限公司 | Hydraulic rubber composite vibration isolation device |
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