The dynamic characteristics of silicone rubber isolator

The dynamic stiffness and the specific damping energy, as well as the vibration response characteristics of a silicone rubber isolator were researched. The results of the vibration test showed that the silicone rubber isolator was excellent in the performance of vibration control. The dynamic stiffness and the damping characteristics were non-linear. From the comparison between experimental results and simulation analysis, the displacement transmissibility characteristics of the isolator were obtained. As a result, the dynamic characteristics of the isolator could be accurately described by the quadratic type non-linear terms at small amplitude.     

金属橡胶隔振系统的研究进展

在数学模型和系统参数识别以及非线性振动理论基础上,建立了一种合理的非线性金属橡胶隔振系统的动力学模型,以便更好地描述这类非线性迟滞系统的动态特性,为工程应用提供了理论基础.     

Research on the Influence of Spring Stiffness on the Electrorheological Isolator

The problem of electrorheological(ER) technology’s application in the vibration isolation system is emphatically studied. Based on the particular characteristics of the electrorheological fluid (ERF) tunable damping, a metal-spring ER isolator is designe     

发动机冷却模块振动优化

针对某轿车搭载直列四缸(L4)发动机型在发动机怠速开空调且冷却风扇处于最高转速2 470 r/m时,方向盘(SW)振动剧烈的问题,对减振连接点和SW的振动进行了振动试验测量,识别出了影响该工况下SW振动的主要因素.运用数值仿真,分析了由冷却模块（CRFM)引起的振动,CRFM系统振动特性数值分析模型的搭建,借助于能量解耦理论和Newmark Beta算法,该模型可分析CRFM搭载不同减振块组合后的模态频率及其在车架振动和风扇振动激励下的响应.振动优化针对搭载不同刚度性能减振连接块的CRFM振动特性进行仿真分析,优化后的CRFM可避开外部激励主要频段,且振动响应较小.     

A novel sensitive piezoelectric mass balance used for weightless environment

A novel sensitive piezoelectric mass balance(PEMB) was developed for using in weightless environment. The mass of the measured object was obtained by detecting the resonant frequency shift of the PEMB. This weighing method was illustrated systematically. In order to build the relationship between the resonant frequency shift and the measured mass, the equivalent stiffness coefficient and the equivalent concentrated mass of the PEMB were analyzed theoretically. The influence of the structural and material parameters on the sensitivity was analyzed, which provided the design reference to improve the sensitivity. The finite-element-method(FEM) static analysis of the PEMB was carried out with ANSYS software to investigate its shock resistance. Furthermore, the vibration test and calibration experiment effectively verified the theoretical analyses results.The developed PEMB holds merits of independence on acceleration field, independence on properties of the measured object and with shock resistance. Consequently, it can be a suitable candidate for measuring mass of solid samples with unknown properties in the weightless environment.     

Torsional stiffness modeling and optimization of the rubber torsion bushing for a light tracked vehicle

Taking the rubber torsion bushing of a certain type of all-terrain tracked vehicle as the research object, a theoretical model of torsional stiffness was proposed according to the non-linear characteristics of rubber components and structural feature of the suspension. Simulations were carried out under different working conditions to obtain root mean square of vertical weighted acceleration as the evaluation index for ride performance of the all-terrain tracked vehicle, with a dynamics model of the whole vehicle based on the theoretical model of the torsional stiffness and standard road roughness as excitation input. Response surface method was used to establish the parametric optimization model of the torsional stiffness. The evaluation index showed that ride performance of the vehicle with optimized torsional stiffness model of suspension was improved compared with previous model from experiment. The torsional stiffness model of rubber bushing provided a theoretical basis for the design of the rubber torsion bushing in light tracked vehicles.     

Design and Testing of a Novel Passive Isolator for a Space Optical Payload

一种用于空间光学载荷隔振的被动式隔振器设计与测试

杨剑锋^1,2,3,黄创绵^1,2,4,王远航^1,3,4,李锴^1,2,4

（1.工业和信息化部电子第五研究所,广州 510610;

2. 广东省电子信息产品可靠性与环境工程技术中心,广州 510610;

3. 广东省电子信息产品可靠性技术重点实验室,广州510610;

4. 广州电子信息产品可靠性与环境工程重点实验室,广州510610）

创新点说明：

本文提出了一种构型新颖的用于空间光学载荷隔振的隔振器,该隔振器具有结构简单、环境适应性强、隔振效果好等优点。通过对其静态特性进行分析,推导得到隔振器的等效刚度模型,考虑到粘弹性阻尼材料其阻尼系数随激励频率和环境温度变化的特点,给出一种基于复刚度模型的分析方法。最后,设计、加工出了一套隔振系统的原理研究,并对其静态性能及隔振性能进行了测试试验。试验结果表明：本文提出的用于粘弹性阻尼材料动力学分析的分析方法有效,计算值与测试结果具有较好的一致性,设计的隔振器可以有效降低传递给光学载荷的振动。

研究目的：

设计一种适用于空间光学载荷在轨隔振的隔振器,并给出其隔振性能的分析方法。

研究方法：

复刚度理论、有限单元法;

试验仪器：HF-10型数显式拉亚测试机,气浮平台,力锤,频谱分析仪。

结果：

静刚度分析值与测试值的最误差大4.21%,最小误差为0.02%,模态分析计算值与测试结果几乎一致,隔振性能分析低频段分析值与测试结果吻合度较好,但高频段出现一定偏差。

结论：

本文设计的隔振器隔振性能较好,能适应不同空间光学载荷的隔振需求,文中提出的用于粘弹性阻尼材料动力学分析的分析方法准确、有效,适用于被动式粘弹性材料隔振器的隔振性能分析。

关键词：隔振器;粘弹性材料; 空间光学载荷

     

铣槽机倾角传感器隔振研究与隔振器设计

铣槽机因切削造成的振动为主要振动,这是影响倾角传感器测量结果的最主要因素.一次隔振并不能减小切削过程中的振动,因而要进行二次隔振以减少对倾角传感器测量的影响,本文将对隔振的基本原理进行阐述,将倾角传感器的振动简化为单自由度模型并进行分析,从倾角传感器的隔振器设计问题出发,分析研究橡胶隔振器的设计参数,从而进行橡胶材料的选择和隔振器结构的设计,为传感器隔振研究及隔振器设计提供依据.     

大跨越输电塔线体系气弹模型风洞试验

针对大跨越输电塔线耦合体系的风振响应问题，以规划中的世界第一高塔--某大跨越输电塔线工程为原型，采用离散刚度法设计制作了塔线体系的气弹模型，并在紊流风场中进行了多个风向角、多个风速下的单塔和塔线体系气弹模型风洞试验.试验结果表明，输电塔的响应可以分解为共振响应与背景响应.通过分析塔线耦合作用对输电塔2部分分量的影响，揭示了塔线体系的风振响应特性.塔线体系与单塔相比，由于阻尼的增加导致共振响应有所降低，而迎风面积的增大使得背景响应有较大幅度的提高.分析塔线体系总的风振响应必须同时考虑塔线耦合作用对2部分分量的影响.     

石英晶体谐振器负载谐振参数测量方法的改进

在基于阻抗计方法测量石英晶体谐振器的负载谐振频率和负载谐振电阻时,由于负载电容的接入造成石英晶体谐振器与负载电容接点对地的高阻抗,使得接点对地分布电容和晶体插座电容成为影响其测量精度的主要原因,这种影响的数量关系可以根据石英晶体谐振器的实际电参数模型导出。采用内置的负载电容并由内置的电容计对等效负载电容实现实时测量,采用间接测量方法测量负载谐振电阻,可显著提高其负载谐振参数的测量精度。     

金属橡胶三维隔振系统共振频率范围限定条件

介绍了金属橡胶隔振器的优越性能，根据金属橡胶隔振器吸收系统给定共振频率限范围与隔振器固定点分布之间的关系，分析了保障系统共振频率在给定范围条件下隔振器刚度变化对固定点分布的影响，得出了隔振器固定平面选取和固定点分布的相关约束条件。     

金属橡胶减振器滞迟特性研究

从摩擦耗能机理出发,利用悬臂梁杆系接触作用模型,推导出金属橡胶减振器循环加载、卸载时载荷和位移的解析表达式,得出理论计算滞迟回线;运用ANSYS有限元分析软件对相对密度不同的环形金属橡胶减振器的变形过程进行数值模拟,得出数值模拟滞迟回线。研究表明,理论计算与数值模拟得到的滞迟回线基本一致,成型相对密度越小耗能特性越大,其刚度越小,软特性阶段越宽。     

胶料硬度对超弹本构模型参数及橡胶弹簧刚度的影响

采用Mooney-Rivlin超弹本构模型,研究不同胶料硬度对超弹本构模型参数及胶料弹簧刚度的影响。对锥形橡胶弹簧进行垂向刚度仿真,并将仿真结果与弹簧刚度试验结果对比,发现不同胶料硬度对橡胶弹簧刚度有显著的影响。利用最小二乘法对现有的离散化数据进行拟合,得出超弹本构模型参数与胶料硬度的函数关系。基于正交试验方法,通过锥形橡胶弹簧刚度仿真试验,求得与实际胶料硬度对应的最佳超弹本构模型参数值C10=0.312,C01=0.087;锥形橡胶弹簧仿真刚度值与试验刚度值的相对误差仅为0.3%,具有较高的精度。     

发动机橡胶悬置有限元模型的建立及实验验证

用Mooney-Rivlin模型描述橡胶材料的本构模型, 通过橡胶单轴压缩试验确定橡胶材料的参数。根据发动机悬置简化模型, 计算预应力和激励频率。用CATIA建立橡胶悬置的三维模型, 在Hypermesh中采用六面体单元进行网格划分, 建立橡胶悬置的有限元模型。利用ANSYS对有限元模型求解, 用Matlab对求解结果进行处理, 根据得到的迟滞回线, 计算出橡胶悬置的静刚度、动刚度和滞后角。利用本文设计的橡胶悬置特性试验测试系统分别对前、后橡胶悬置进行静、动刚度试验, 将试验得到的橡胶悬置静、动刚度结果与有限元计算结果进行对比, 验证了有限元模型的正确性。       

囊式空气弹簧隔振器动态特性影响因素分析

利用MTS材料试验机测试囊式空气弹簧隔振器的动态特性,并研究了充气气压和振动频率对隔振器动刚度的影响.结果表明,囊式空气弹簧隔振器的动刚度与充气气压基本成线性关系,与振动频率也基本是线性关系.     

Calculation of resonant sound absorption parameters for performance evaluation of metal rubber material

The first resonant (anti-resonant) frequency and sound absorption coefficient of metal rubber (MR) material are theoretically studied with hard backed samples and with air layer. The equations of the first resonant and anti-resonant frequencies of MR are deduced from the undamped propagation characteristics of porous material. The first resonant and anti-resonance sound absorption coefficients are induced according to the theoretical formula for the acoustic characteristic parameters of MR, and the former is modified while the energy consumption at resonance is taken into consideration. The good agreement between the calculation results of these resonant sound absorption parameters and the experimental results verifies the effectiveness of this calculation method for the performance evaluation of MR as a sound absorption material.     

橡胶隔震支座拉伸性能试验研究

为了正确评价橡胶隔震支座拉伸性能以及拉伸状态时计算模型的合理性,基于橡胶隔震支座拉伸应力应变关系曲线,提出了拉伸刚度应力应变关系的计算模型,对橡胶隔震支座竖向拉力和拉伸变形性能,拉伸剪切变形状态下偏拉原点刚度、水平刚度和阻尼与剪切应变关系进行了试验研究.结果表明,本文建立的计算模型与试验结果吻合较好.因此,在隔震支座所受拉伸应力不大于3倍橡胶剪切模量的条件下,支座的力学性能稳定.     

悬臂梁结合面建模与接触刚度参数识别

基于有限单元法,将结合面简化为一系列包含接触刚度的参数单元,建立了包含结合面的悬臂梁实验模型的有限元模型。根据实验测试所获得的前两阶固有频率,结合所建立的接触刚度参数优化识别的目标函数,利用MATLAB优化工具箱,对结合面在不同面压下的法向接触刚度参数进行了优化识别,获得了不同面压条件下单位结合面上的法向接触刚度参数值,从而为下一步的理论计算与实际应用奠定了基础。     

Research on Noise Control for Ventilators with Resonance

A study was carried out to control the noise produced by the ventilators at the Luling coalmine, which had caused serious noise pollution to the residents living around the mine for a long time. The main noise source was found to be the dynamic noise at the outlet of the diffuser. The frequency of its peak value was 250 Hz, A special brick with a resonant frequency of 250 Hz was designed to eliminate this noise. The diffusion of a lower frequency noise has been successfully controlled by the installation of a noise-eliminating tower above the diffuser outlet. The detection results show that the noise in the nearby residential area has been lowered to an average 55.3dB（A） in the daytime from 69.8dB（A） and to 48.4dB（A） at night from 65.8dB（A）.     

梁结构疲劳刚度退化对模态频率的影响

为了研究梁结构疲劳刚度退化对模态频率的影响,对预应力混凝土梁进行疲劳试验和动力测试,得到疲劳历程中疲劳刚度和模态频率的演化规律. 建立疲劳全过程变刚度有限元修正模型,并对其进行模态分析. 比较分析试验和模拟结果,讨论模态频率退化规律及疲劳刚度退化对其影响机制. 研究结果表明,梁结构模态频率具有类似抗弯刚度退化的三阶段衰减规律,表明疲劳刚度与模态频率退化存在映射关系;在疲劳作用下,第1阶频率的下降幅度最大,第2阶频率次之,第3阶频率的下降幅度最小;提出的变刚度假设在有限元模拟中运用良好,模拟结果显示第1阶频率模拟值的偏差基本在10%以内. 提出的疲劳全过程动力特性分析方法为梁结构疲劳分析研究提供了新思路.