连接结构微振动传递机理实验探究
发布时间：2019-04-10 12:55
【摘要】：由于外太空微小陨石的撞击,太阳辐射压力等复杂的环境背景因素以及姿态机动,卫星变轨,载荷启动与停止等等因素,经常会导致在轨卫星产生相应的动力学响应,所引起相应的结构频率高达1000Hz,幅值低于10-1g,这个过程被称之为微振动干扰。螺栓连接和胶接连接作为航天器平台中最常见的两种连接方式,对微振动的传递起着非常重要的作用。早期的动力学研究中,常常将结合面看成是刚性接触,即不存在相对运动,但是随着研究的深入,人们发现,连接处的螺栓和树脂胶是航天器平台上无源阻尼和非线性刚度的主要来源。螺栓和胶接连接结构会影响整体结构的固有频率,模态振型,阻尼等等,从而使其表现出非线性的力学特性,因此对螺栓以及胶接固定结合面进行深入研究具有尤为重要的现实意义。根据前人对连接界面滑移耗能现象的研究,在理论方面,本文对承受剪力螺栓连接件简化模型的耗能公式进行了推导,得出了在该研究条件下,模型的力-相对位移解析表达式,并且通过Matlab软件画出了相应迟滞回线图形,通过代入不同的压强模型,最终得到耗能与激励力,耗能与相对位移所存在的幂次方关系。为了得到相应加工试件的模态参数,即获取结构的固有频率、振型和阻尼比我对加工好的实验试件进行了试验模态分析。针对前面的理论分析,我还对相应的多组螺栓和胶接连接结构的实体试件进行了实验方面的研究。实验过程中,利用激振器来提供外界的激励力,通过力传感器,加速度传感器,LMS数据采集系统来采集分析处理相应的信号。整个过程中,通过改变不同的扭矩,频率,激励力大小来对实验试件进行对比实验测试。最终获取不同实验条件下的加速度值和力值的数据。再利用Origin软件对加速度数据进行两次积分处理,得到位移数据,将数据最终进行汇总,相应的就可以得到螺栓和胶接连接结构的能量耗散与激励力和相对位移的关系图像,并与上面提到的理论公式进行对比分析,最终得出结论。
[Abstract]:Due to the impact of small meteorite in outer space, complex environmental background factors such as solar radiation pressure, attitude maneuver, satellite orbit change, load start-up and stop, and so on, it often leads to the corresponding dynamic response of in-orbit satellites. The frequency of the structure is as high as 1000 Hz and the amplitude is less than 10 渭 g. This process is called micro-vibration interference. As the two most common connecting modes of spacecraft platform, bolted connection and glued joint play a very important role in the transmission of micro-vibration. In the early study of dynamics, the interface is often regarded as rigid contact, that is, there is no relative motion, but with the deepening of the study, people find that, The bolt and resin glue at the joint are the main sources of passive damping and nonlinear stiffness on spacecraft platform. The bolted-bonded structure will affect the natural frequency, modal mode shape, damping and so on of the whole structure, so as to show the nonlinear mechanical properties of the whole structure. Therefore, it is of great practical significance to study the bolt and fixed bonding surface in depth. According to the previous research on the slip energy dissipation phenomenon of the joint interface, in the theoretical aspect, the energy dissipation formula of the simplified model of the shear bolt connector is derived, and the results show that under the condition of this research, the energy dissipation formula of the shear bolt joint is obtained. The analytical expression of force-relative displacement of the model is given, and the corresponding hysteresis loop graph is drawn by Matlab software. Finally, the power relation between energy dissipation and excitation force, energy dissipation and relative displacement is obtained by substituting different pressure models. In order to obtain the modal parameters of the machined specimen, that is, to obtain the natural frequency of the structure, the modal shape and damping ratio I have carried on the experimental modal analysis to the well-machined experimental specimen. In view of the previous theoretical analysis, I also made an experimental study on the corresponding groups of solid specimens of bolted and bonded structures. During the experiment, the exciter is used to provide the external excitation force. The corresponding signals are collected, analyzed and processed by force sensor, acceleration sensor and LMS data acquisition system. In the whole process, different torque, frequency and excitation force are changed to test the experimental samples. Finally, the data of acceleration value and force value under different experimental conditions are obtained. Then the acceleration data are processed twice with Origin software, and the displacement data is obtained. Finally, the data are summarized, and the corresponding image of the relation between the energy dissipation and the excitation force and the relative displacement of the bolt-to-glue connection structure can be obtained. And compared with the theoretical formula mentioned above, the final conclusion is drawn.
【学位授予单位】：北京理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：V414
本文编号：2455814
[Abstract]:Due to the impact of small meteorite in outer space, complex environmental background factors such as solar radiation pressure, attitude maneuver, satellite orbit change, load start-up and stop, and so on, it often leads to the corresponding dynamic response of in-orbit satellites. The frequency of the structure is as high as 1000 Hz and the amplitude is less than 10 渭 g. This process is called micro-vibration interference. As the two most common connecting modes of spacecraft platform, bolted connection and glued joint play a very important role in the transmission of micro-vibration. In the early study of dynamics, the interface is often regarded as rigid contact, that is, there is no relative motion, but with the deepening of the study, people find that, The bolt and resin glue at the joint are the main sources of passive damping and nonlinear stiffness on spacecraft platform. The bolted-bonded structure will affect the natural frequency, modal mode shape, damping and so on of the whole structure, so as to show the nonlinear mechanical properties of the whole structure. Therefore, it is of great practical significance to study the bolt and fixed bonding surface in depth. According to the previous research on the slip energy dissipation phenomenon of the joint interface, in the theoretical aspect, the energy dissipation formula of the simplified model of the shear bolt connector is derived, and the results show that under the condition of this research, the energy dissipation formula of the shear bolt joint is obtained. The analytical expression of force-relative displacement of the model is given, and the corresponding hysteresis loop graph is drawn by Matlab software. Finally, the power relation between energy dissipation and excitation force, energy dissipation and relative displacement is obtained by substituting different pressure models. In order to obtain the modal parameters of the machined specimen, that is, to obtain the natural frequency of the structure, the modal shape and damping ratio I have carried on the experimental modal analysis to the well-machined experimental specimen. In view of the previous theoretical analysis, I also made an experimental study on the corresponding groups of solid specimens of bolted and bonded structures. During the experiment, the exciter is used to provide the external excitation force. The corresponding signals are collected, analyzed and processed by force sensor, acceleration sensor and LMS data acquisition system. In the whole process, different torque, frequency and excitation force are changed to test the experimental samples. Finally, the data of acceleration value and force value under different experimental conditions are obtained. Then the acceleration data are processed twice with Origin software, and the displacement data is obtained. Finally, the data are summarized, and the corresponding image of the relation between the energy dissipation and the excitation force and the relative displacement of the bolt-to-glue connection structure can be obtained. And compared with the theoretical formula mentioned above, the final conclusion is drawn.
【学位授予单位】：北京理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：V414
【参考文献】
相关期刊论文 前1条
1 赵伟;;航天器微振动环境分析与测量技术发展[J];航天器环境工程;2006年04期
，本文编号：2455814
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