This paper investigates the damping and demagnetization effect of an electromagnetic buffer (EMB) under impact load. The motional eddy currents are calculated first, and the Ampere circuital theorem is employed to calculate the induced magnetic field. The demagnetization effect is formulated by themagnetic Reynolds number with a correction coefficient km. Following this, the time-step finite element (FE) model of the buffering system is constructed based on the nonlinear B–H curve. The accuracy and feasibility of the FE model is preliminarily verified by small-scale impact test. The characteristics of damping displacement, velocity, damping force and damping coefficient are obtained. Then, the demagnetization effect is analysed by eddy current, magnetic field distribution, through the intensive impact load test at room temperature and time-step FE model. The value of km is obtained through the intensive impact test and the simplified expression of critical velocity. The results show that the demagnetization effect is obvious with the increase of velocity. By introducing the correction coefficient of magnetic Reynolds number, the eddy current demagnetization process is more realistic.

中文翻译：

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圆柱线性电磁缓冲器在冲击载荷作用下的阻尼和退磁分析

本文研究了冲击载荷下电磁缓冲器（EMB）的阻尼和消磁作用。首先计算运动涡流，然后采用安培电路定理计算感应磁场。消磁效果由具有校正系数km的雷诺数表示。在此之后，基于非线性B–H曲线构造了缓冲系统的时步有限元（FE）模型。通过小规模冲击试验初步验证了有限元模型的准确性和可行性。获得了阻尼位移，速度，阻尼力和阻尼系数的特性。然后，通过涡流，磁场分布，通过在室温和时间步长有限元模型下的强烈冲击载荷测试。km的值是通过强烈的冲击试验和临界速度的简化表达式获得的。结果表明，随着速度的增加，去磁效果明显。通过引入雷诺数校正系数，使涡流退磁过程更加现实。