### 抄録

This research deals with nonlinear dynamics of a rotating rigid magnet levitated above a high T_{c} superconducting (HTSC) bulk. Motion of the rotating magnet in the radial and axial directions were investigated theoretically by using analytical expression of electromagnetic force obtained by “the advanced mirror image method”. Analytical and numerical results show existence of combination resonance due to nonlinear coupling between whirling and vertical motion of the magnet. The resonant frequency of rotation is given as the sum of the natural frequency in the horizontal and vertical directions. At this resonance, the whirling motion becomes quasi-periodic, having the harmonics with both the driving and natural frequencies, while periodic motion at the natural frequency appears in the vertical direction. Stability analysis shows that this resonance occurs if the eccentricity of the magnet is larger than a certain critical value. Experiments for spinning motion of the magnet were carried out, and combination resonance predicted in the theory was clearly observed. Nonlinearity in forces can thus have significant effects on dynamics in application of HTSC bearings.

元の言語 | English |
---|---|

ページ（範囲） | 3568-3575 |

ページ数 | 8 |

ジャーナル | Nihon Kikai Gakkai Ronbunshu, C Hen/Transactions of the Japan Society of Mechanical Engineers, Part C |

巻 | 66 |

発行部数 | 651 |

DOI | |

出版物ステータス | Published - 2000 |

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### ASJC Scopus subject areas

- Mechanics of Materials
- Mechanical Engineering
- Industrial and Manufacturing Engineering

### これを引用

_{c}Superconducting Bearing.

*Nihon Kikai Gakkai Ronbunshu, C Hen/Transactions of the Japan Society of Mechanical Engineers, Part C*,

*66*(651), 3568-3575. https://doi.org/10.1299/kikaic.66.3568

**Combination Resonance of a Rotor Supported by a High-T _{c} Superconducting Bearing.** / Sugiura, Toshihiko; Matsunaga, Keniti; Kugiya, Takuo; Yoshizawa, Masatsugu.

研究成果: Article

_{c}Superconducting Bearing',

*Nihon Kikai Gakkai Ronbunshu, C Hen/Transactions of the Japan Society of Mechanical Engineers, Part C*, 巻. 66, 番号 651, pp. 3568-3575. https://doi.org/10.1299/kikaic.66.3568

_{c}Superconducting Bearing. Nihon Kikai Gakkai Ronbunshu, C Hen/Transactions of the Japan Society of Mechanical Engineers, Part C. 2000;66(651):3568-3575. https://doi.org/10.1299/kikaic.66.3568

}

TY - JOUR

T1 - Combination Resonance of a Rotor Supported by a High-Tc Superconducting Bearing

AU - Sugiura, Toshihiko

AU - Matsunaga, Keniti

AU - Kugiya, Takuo

AU - Yoshizawa, Masatsugu

PY - 2000

Y1 - 2000

N2 - This research deals with nonlinear dynamics of a rotating rigid magnet levitated above a high Tc superconducting (HTSC) bulk. Motion of the rotating magnet in the radial and axial directions were investigated theoretically by using analytical expression of electromagnetic force obtained by “the advanced mirror image method”. Analytical and numerical results show existence of combination resonance due to nonlinear coupling between whirling and vertical motion of the magnet. The resonant frequency of rotation is given as the sum of the natural frequency in the horizontal and vertical directions. At this resonance, the whirling motion becomes quasi-periodic, having the harmonics with both the driving and natural frequencies, while periodic motion at the natural frequency appears in the vertical direction. Stability analysis shows that this resonance occurs if the eccentricity of the magnet is larger than a certain critical value. Experiments for spinning motion of the magnet were carried out, and combination resonance predicted in the theory was clearly observed. Nonlinearity in forces can thus have significant effects on dynamics in application of HTSC bearings.

AB - This research deals with nonlinear dynamics of a rotating rigid magnet levitated above a high Tc superconducting (HTSC) bulk. Motion of the rotating magnet in the radial and axial directions were investigated theoretically by using analytical expression of electromagnetic force obtained by “the advanced mirror image method”. Analytical and numerical results show existence of combination resonance due to nonlinear coupling between whirling and vertical motion of the magnet. The resonant frequency of rotation is given as the sum of the natural frequency in the horizontal and vertical directions. At this resonance, the whirling motion becomes quasi-periodic, having the harmonics with both the driving and natural frequencies, while periodic motion at the natural frequency appears in the vertical direction. Stability analysis shows that this resonance occurs if the eccentricity of the magnet is larger than a certain critical value. Experiments for spinning motion of the magnet were carried out, and combination resonance predicted in the theory was clearly observed. Nonlinearity in forces can thus have significant effects on dynamics in application of HTSC bearings.

KW - Combination Resonance

KW - Coupled Vibration

KW - Electromagnetic Force

KW - High-Tc Superconducting Bearing

KW - Nonlinear Vibration

KW - Vibration of Rotating Body

UR - http://www.scopus.com/inward/record.url?scp=85024461951&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85024461951&partnerID=8YFLogxK

U2 - 10.1299/kikaic.66.3568

DO - 10.1299/kikaic.66.3568

M3 - Article

AN - SCOPUS:85024461951

VL - 66

SP - 3568

EP - 3575

JO - Nihon Kikai Gakkai Ronbunshu, C Hen/Transactions of the Japan Society of Mechanical Engineers, Part C

JF - Nihon Kikai Gakkai Ronbunshu, C Hen/Transactions of the Japan Society of Mechanical Engineers, Part C

SN - 0387-5024

IS - 651

ER -