The research of magnetic damper for vibration reduction of 3D whirling motion

3D旋转运动减振磁阻尼器研究

基本信息

批准号：
16560212
负责人：
TAKAYAMA Yoshihisa
金额：
$ 2.13万
依托单位：
Kyushu University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2004
资助国家：
日本
起止时间：
2004 至 2007
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-16560212/
关键词：
magnetic damper eddy current damper Fleming's right-hand rule Fleming's left-hand rule eddy current 回転体

项目摘要

When a conducting plate moves through a nonuniform magnetic field, eddy currents are induced in the conducting plate. Using Fleming's right-hand and left-hand rule, we can explain that the eddy currents produce a magnetic drag force. In those rules, a magnetic field perpendicular to the direction of movement generates a magnetic damping force.We have fabricated the magnetic damper composed of the spherical magnet and the conducting shell. The spherical magnet produces the axisymmetric magnetic field, and the shape of the conducting shell appears to combine a semispherical shell conductor and a cylinder conductor. When the eddy current damper works, the conducting shell is fixed in space, and the spherical magnet moves under the conducting shell. And also we have fabricated the magnetic damper consisting of a hollow-cylindrical conducting plate and a ring-shaped magnet. The ring shaped magnet produces the axisymmetric magnetic field.In those cases, since there are magnetic flux densities perpendicular to the direction of movement, eddy currents flow inside the conductor, and then a magnetic force is produced. The reaction force of this magnetic force acts on the magnet. In our study, magnetic dampers composed of a magnet and a conductor have been modeled using infinitesimal loop coils. As a result, magnetic damping forces are obtained. Our modeling has three merits as follows: the equation of a magnetic damping force is simple in the equation, we can use the static magnetic field obtained using FEM, the Biot-Savart law or experiments and the equation automatically satisfies boundary conditions using infinitesimal loop coils. The analytical results of the modeling agree well with the experimental results.

当导电板穿过不均匀磁场时，导电板中会产生涡流。使用弗莱明右手和左手定则，我们可以解释涡流产生磁阻力。在这些规则中，垂直于运动方向的磁场产生磁阻尼力。我们制造了由球形磁体和导电壳组成的磁阻尼器。球形磁体产生轴对称磁场，导电壳的形状似乎结合了半球壳导体和圆柱体导体。涡流阻尼器工作时，导电壳固定在空间中，球形磁体在导电壳下方运动。我们还制作了由空心圆柱形导电板和环形磁体组成的磁阻尼器。环形磁铁产生轴对称磁场。在这种情况下，由于存在垂直于运动方向的磁通密度，因此导体内部会产生涡流，从而产生磁力。该磁力的反作用力作用在磁铁上。在我们的研究中，使用无穷小环形线圈对由磁体和导体组成的磁阻尼器进行了建模。结果，获得磁阻尼力。我们的建模具有以下三个优点：磁阻尼力的方程简单，我们可以使用通过有限元、毕奥-萨伐尔定律或实验获得的静磁场，并且使用无穷小环形线圈，方程自动满足边界条件。模型分析结果与实验结果吻合较好。