关键词: 振动与波, 电涡流阻尼器, 减振, 阻尼特性, 有限元

Abstract:

In order to satisfy the requirements of vibration condition for those sophisticated components mounted in spacecraft, it is necessary to attenuate the vibration. Since the spacecraft works in a harsh environment with high vacuum and large temperature difference, the dampers used in it must have enough reliability. This paper aims to propose a novel eddy current damper used for attenuating vibration in spacecraft, which mainly includes two copper plates, one cylinder magnets and an electromagnetic shielding case. Firstly, Based based on the numerical simulation the magnetic field and mechanical finite element model are established to analyze the vibration damping characteristics of the eddy current damper. Moreover, a simulation method based on the three-dimensional electromagnetic transient analysis in ANSYS is proposed. The damping characteristics is tested on the vibration experiment table, where the sinusoidal excitation with amplitudes of 0.1mm and 1mm are applied when the frequency range is 1 ~ 50Hz. Then the mechanical analysis model of the damper is established according to the Bouc-Wen hysteretic theory. Meanwhile, the relationship among the loading, the damper structure and the alternating Lorentz force is studied. The results show that this new type of eddy current damper can output a damping force under applied load, which is closer to the simulation results. The relationship between the damping coefficient and the excitation frequency is obtained. In addition, the simulation and experimental results show that the damping performance of proposed current damper is much better than that of the eddy current damper with only one plate, which verifies the correctness of structure of the eddy current damper. The presented model can be well used to reflect the mechanical properties of eddy current damper.