We have analyzed the effect of geomagnetic field and testing environment of fatigue specimen magnetic memory testing signals and the changes of specimen from integer to parting on the basis of the mechanism of magnetism effect 摘要根据磁效应机理,分析了地磁场和检测环境对疲劳试件磁记忆检测结果的影响,以及试件断裂前后磁记忆检测信号的变化。
Satellites are providing clear snapshots of the geomagnetic field at the earth ' s surface , while new strategies for simulating earthlike dynamos on supercomputers and creating physical models in the laboratory are elucidating those orbital observations 人造卫星能清楚拍摄地表磁场的图像;而利用超级电脑来模拟地球发电机,以及在实验室里建立的物理模型,则解释了轨道上的观测结果。
According to the mean field theory which is based on the phenomenological theory of ferromagnetism , using the conception of effective magnetic field , an effective magnetic field expression for ferromagnetism rod affected by stress in the geomagnetic field is derived 基于铁磁性的唯像理论,根据分子场理论,利用有效场的概念,得到了地磁场中受应力作用的铁磁杆件的有效场表达式。
When reconnection is initiated on the dayside magnetopause , the interconnected imf and geomagnetic field lines are swept back by the solar wind over the earth ' s poles , pouring energy into the northern and southern lobes of the long magnetotail on the nightside 当磁力线重连在昼侧的磁层顶上开始发生,连在一起的imf和地球磁场磁力线便被太阳风往后吹,扫过地球南北极,把能量灌入长磁尾的南北两叶。
In this application , the lorentz force generated by the interaction between the current in the wire and the geomagnetic field produces an electro - dynamic drag leading to a fast orbital decay . in this paper , we make an intensive study of the process of de - orbiting using electro - dynamic tether system . the concrete work includes : firstly , i have studied the basic principle of how to generate the electro - dynamic drag , modeled via accuracy geomagnetism , made a concrete analysis of the de - orbiting duration , the magnitude and direction of electro - dynamic drag under the action of the dipole and accurate geomagnetic models , set up a counterbalance between electro - dynamic torque and gravity gradient torque , emulate the de - orbiting process of spacecraft , and compared the change of six orbital factors and the de - orbiting duration under the action of the dipole and accurate geomagnetic models 本文对基于电动力缆绳的航天器离轨过程进行了深入研究,具体工作如下:首先,本文研究了电动力缆绳产生电动力拉力的基本原理,建立了精确地磁场模型;分别在偶极子模型和精确地磁场模型作用下,对电动力拉力的大小、方向、离轨时间及电动力缆绳倾角的大小进行了计算分析;建立了电动力力矩与缆绳系统重力梯度力矩的平衡关系;分析了电动力力矩为系统提供能量的原理;最后分别在偶极子地磁场模型和精确地磁场模型作用下,对受电动力缆绳作用的航天器的离轨过程进行仿真,分析了在不同精度地磁场模型下,航天器离轨过程中各轨道参数的变化情况,并比较了不同模型对离轨时间的影响。
The theoretical analysis and experiment outcome indicate that geomagnetic field and testing environment have momentous effect on testing outcome , that specimen should be laid transmeridionally as soon as possible while testing and that the swing value and crossing zero line of metal magnetic memory signals before and after fatigued specimen cracking will change or move 理论分析和实验结果表明:地磁场和检测环境对检测结果会产生较大影响,检测时应尽可能将试件东西方向放置;疲劳试件断裂前后的磁记忆信号的幅值和过“ 0 ”线将发生变化。
Increased radiation from the sun and occurrence of geomagnetic storms i . e . severe distortion of geomagnetic field of the earth may cause disturbances such as increases in density in the earth s upper atmosphere . these result in a greater drag on the movement of satellites and spacecraft , causing a slow - down or even a change in orbit 辐射的增加及地磁暴即地球磁场急速变形的出现,会导致地球上层大气的扰动,例如空气密度的上升,从而使卫星和太空船在航行时受到的阻力大增,航行速度因而减慢,甚至轨道亦会改变。
According to faraday law on electromagnetic induction and the difference of the magnetic energy of ferromagnetic materials in their magnetization and demagnetization , it is clarified that the swing , vibration and periodic translational reciprocation of any object made of ferromagnetic material in geomagnetic field must cause spontaneous magnetization of the object itself 摘要依据法拉第电磁感应定律和铁磁性物质在磁化一退磁过程中的能量差异,阐明了铁磁性物体在地磁场中的摆动、振动和周期性往复平动都会引起该物体的自发磁化。
Increased radiation from the sun and occurrence of geomagnetic storms ( i . e . severe distortion of geomagnetic field of the earth ) may cause disturbances such as increases in density in the earth s upper atmosphere . these result in a greater drag on the movement of satellites and spacecraft , causing a slow - down or even a change in orbit 辐射的增加及地磁暴(即地球磁场急速变形)的出现,会导致地球上层大气的扰动,例如空气密度的上升,从而使卫星和太空船在航行时受到的阻力大增,航行速度因而减慢,甚至轨道亦会改变。
Using piezoresistive accelerometers and magnetoresistance sensors measure the dynamic acceleration and geomagnetic field and through avr mcu software to calculate the attitude angular and azimuth . the fact of affecting the module is discussed in detail in this report and put forward the resolving scheme of key technology of digital filter , linear compensation , temperature compensation and magnetic field adjustment . the digital module has advantages of small size , light weight , low conception , high accuracy , all solid state and high reliability 本课题采用压阻式加速度计和磁阻传感器分别测量重力加速度和地磁场,通过avrmcu软件解算出姿态角和方位角,课题详细分析了影响模块性能指标的因素,就数字滤波、线性补偿、温度补偿、磁场修正等关键的技术问题提出了可行的解决方案,研制的数字化模块具有体积小、重量轻、低功耗、精度高、全固态、高可靠等特点,所有性能指标均满足设计要求,为姿态角测量提供了有效的手段。