Topology optimization of the permanent magnet type MRI considering the magnetic field homogeneity

Junghoon Lee, Jeonghoon Yoo

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

This study is to suggest a concept design of the permanent magnet (PM) type magnetic resonance imaging (MRI) device based on the topology optimization method. The pulse currents in the gradient coils in the MRI device will introduce the effect of eddy currents in ferromagnetic material and it may worsen the quality of imaging. To equalize the magnetic flux in the PM type MRI device for good imaging, the eddy current effect in the ferromagnetic material must be reduced. This study attempts to use the topology optimization scheme for equalizing the magnetic flux in the measuring domain of the PM type MRI device using that the magnetic flux can be calculated directly by a commercial finite element analysis package. The density method is adopted for topology optimization and the sensitivity of the objective function is computed according to the density change of each finite element in the design domain. As a result, optimal shapes of the pole of the PM type MRI device can be obtained. The commercial package, ANSYS, is used for analyzing the magnetic field problem and obtaining the resultant magnetic flux.

Original languageEnglish
Pages (from-to)1651-1654
Number of pages4
JournalJournal of Magnetism and Magnetic Materials
Volume322
Issue number9-12
DOIs
Publication statusPublished - 2010 May 1

Fingerprint

Shape optimization
Magnetic resonance
permanent magnets
Permanent magnets
homogeneity
magnetic resonance
topology
magnetic flux
Magnetic fields
Imaging techniques
optimization
Magnetic flux
magnetic fields
ferromagnetic materials
eddy currents
Ferromagnetic materials
Eddy currents
poles
coils
gradients

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

Cite this

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Topology optimization of the permanent magnet type MRI considering the magnetic field homogeneity. / Lee, Junghoon; Yoo, Jeonghoon.

In: Journal of Magnetism and Magnetic Materials, Vol. 322, No. 9-12, 01.05.2010, p. 1651-1654.

Research output: Contribution to journalArticle

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