Unstable vibration of a rotating machine caused by a magnetic damping force

Yoshihisa Takayama, Atsuo Sueoka, Takahiro Kondou, Naoyuki Nagai

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

Using the infinitesimal loop model that is moving through the nonuniform magnetic field in space, the effective expression of the magnetic damping force is derived. This method has an advantage of calculating no scalar potential and it is easy to compute the magnetic damping force by using the static magnetic field obtained by FEM, measurements and so on. By the way, a magnetic damper used in turbo-molecular pump and so on in order to reduce vibration sometimes generates unstable vibrations. In this report, it was made clear that the Jeffcot rotor with the magnetic damper generated the unstable vibration in the experiment over a critical speed, and the present method was available for investigating the cause of the unstable vibration due to asymmetric stiffness matrix. Then a good agreement between the analytical and experimental results was confirmed.

Original languageEnglish
Pages (from-to)16-23
Number of pages8
JournalNihon Kikai Gakkai Ronbunshu, C Hen/Transactions of the Japan Society of Mechanical Engineers, Part C
Volume68
Issue number1
Publication statusPublished - Jan 2002

Fingerprint

Damping
Magnetic fields
Stiffness matrix
Rotors
Pumps
Finite element method
Experiments

All Science Journal Classification (ASJC) codes

  • Mechanical Engineering

Cite this

@article{50089b0223804744b35fa4ac2c0e12e7,
title = "Unstable vibration of a rotating machine caused by a magnetic damping force",
abstract = "Using the infinitesimal loop model that is moving through the nonuniform magnetic field in space, the effective expression of the magnetic damping force is derived. This method has an advantage of calculating no scalar potential and it is easy to compute the magnetic damping force by using the static magnetic field obtained by FEM, measurements and so on. By the way, a magnetic damper used in turbo-molecular pump and so on in order to reduce vibration sometimes generates unstable vibrations. In this report, it was made clear that the Jeffcot rotor with the magnetic damper generated the unstable vibration in the experiment over a critical speed, and the present method was available for investigating the cause of the unstable vibration due to asymmetric stiffness matrix. Then a good agreement between the analytical and experimental results was confirmed.",
author = "Yoshihisa Takayama and Atsuo Sueoka and Takahiro Kondou and Naoyuki Nagai",
year = "2002",
month = "1",
language = "English",
volume = "68",
pages = "16--23",
journal = "Nippon Kikai Gakkai Ronbunshu, C Hen/Transactions of the Japan Society of Mechanical Engineers, Part C",
issn = "0387-5024",
publisher = "The Japan Society of Mechanical Engineers",
number = "1",

}

TY - JOUR

T1 - Unstable vibration of a rotating machine caused by a magnetic damping force

AU - Takayama, Yoshihisa

AU - Sueoka, Atsuo

AU - Kondou, Takahiro

AU - Nagai, Naoyuki

PY - 2002/1

Y1 - 2002/1

N2 - Using the infinitesimal loop model that is moving through the nonuniform magnetic field in space, the effective expression of the magnetic damping force is derived. This method has an advantage of calculating no scalar potential and it is easy to compute the magnetic damping force by using the static magnetic field obtained by FEM, measurements and so on. By the way, a magnetic damper used in turbo-molecular pump and so on in order to reduce vibration sometimes generates unstable vibrations. In this report, it was made clear that the Jeffcot rotor with the magnetic damper generated the unstable vibration in the experiment over a critical speed, and the present method was available for investigating the cause of the unstable vibration due to asymmetric stiffness matrix. Then a good agreement between the analytical and experimental results was confirmed.

AB - Using the infinitesimal loop model that is moving through the nonuniform magnetic field in space, the effective expression of the magnetic damping force is derived. This method has an advantage of calculating no scalar potential and it is easy to compute the magnetic damping force by using the static magnetic field obtained by FEM, measurements and so on. By the way, a magnetic damper used in turbo-molecular pump and so on in order to reduce vibration sometimes generates unstable vibrations. In this report, it was made clear that the Jeffcot rotor with the magnetic damper generated the unstable vibration in the experiment over a critical speed, and the present method was available for investigating the cause of the unstable vibration due to asymmetric stiffness matrix. Then a good agreement between the analytical and experimental results was confirmed.

UR - http://www.scopus.com/inward/record.url?scp=0036414109&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0036414109&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:0036414109

VL - 68

SP - 16

EP - 23

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

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

SN - 0387-5024

IS - 1

ER -