Abstract
Contact force is related to the mechanical response of superconducting strands under a large electromagnetic body force, which is important for the safety of the international thermonuclear experimental reactor (ITER) magnet structure. Due to the complex structure of the cable-in-conduit conductor (CICC), the component unit of the ITER magnet, and the extreme operating environment, the research on the strand contact force caused by the electromagnetic force has been progressing slowly. In this study, a two-dimensional (2D) theoretical model based on the granular element method is constructed to compute the contact forces among some opaque and non-photoelastic ferromagnetic particles which are placed in a non-uniform magnetic field. In the experiment, the contact deformations of these particles may be obtained by the digital image correlation method. We also propose a method, which is similar to the least-squares method, to calculate the electromagnetic body forces of different particles. Subsequently, the distributional and statistical characteristics of the contact force chains and contact angles are presented. It is considered that the method proposed in this paper is suitable for the contact force analysis of the cross section of superconducting strands in the ITER CICC that is subjected to a transverse electromagnetic force. In the end, this 2D theoretical model is generalized to the three-dimensional (3D) case, and the concise mathematical framework is presented.
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This work is supported by the fund of Natural Science Foundation of China (Nos. 11872196, 11902130).
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Jiao, S., Liu, C., Zhou, J. et al. Extraction on the Contact Forces Among the Opaque and Non-photoelastic Particles Under Electromagnetic Force. Acta Mech. Solida Sin. 35, 248–260 (2022). https://doi.org/10.1007/s10338-021-00293-1
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DOI: https://doi.org/10.1007/s10338-021-00293-1