Mechanics of a Composite Structure of GFRP Insulators and Superconductors with a GAP
Superconducting coils in large scale magnet applications such as the Large Helical Device (LHD) are subjected to large electromagnetic force at the interfaces between conductors and electrical insulators. The insulators do not always contact the superconductor surfaces completely. This may cause a reduction of coil rigidity. Nonlinear behavior was observed in the compressive load-displacement curves in some experiments of coil packs. The nonlinear curves were found to be well fitted by an exponential function. We considered this nonlinearity as a surface contact problem and devised some analytical models to evaluate the rigidity reduction in terms of gap length. The results of this analysis also support the exponential function.
KeywordsGlass Fiber Reinforce Plastic Helical Coil Superconducting Coil Coil Pack Fusion Engineer
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- 1.O. Motojima, K. Akaishi, K. Fujii, S. Fujiwaka, S. Imagawa, H. Ji, H. Kanako, S. Kitagawa, Y. Kubota, K. Matsuoka, T. Mito, S. Morimoto, A. Nishimura, K. Nishimura, N. Noda, I. Ohtake, N. Ohyabu, S. Okamura, A. Sagara, M. Sakamoto, S. Satoh, T. Satow, K. Takahata, H. Tamura, S. Tanahashi, T. Tsuzuki, S. Yamada, H. Yamada, K. Yamazaki, N. Yanagi, H. Yonezu, J. Yamamoto, M. Fujiwara and A. Iiyoshi, Physics and engineering design studies on the Large Helical Device, Fusion Engineering and Design, 20: 3 (1993).CrossRefGoogle Scholar
- 2.J. Yamamoto, T. Mito, O. Motojima, K. Takahata, N. Yanagi, S. Yamada, A. Nishimura, M. Sakamoto, H. Tamura, S. Imagawa, S. Satow, M. Takeo, M. Fujiwara and A. Iiyoshi, A. Research and Development of Superconductors and Superconducting Coils for the Large Helical Device, Fusion Engineering and Design, 20: 139 (1993).CrossRefGoogle Scholar
- 4.A. Nishimura, H. Tamura, S. Imagawa, T. Mito, K. Takahata, J. Yamamoto, S. Mizumaki, H. Ogata, H. Takano, Experimental Rigidity Evaluation of Conduit Pack for Forced-Flow Superconducting Coil, Advances in Cryogenic Engineering 40: 1413 (1994).Google Scholar
- 5.Y. Shindo, Y. Takagi, H. Tamura, A. Nishimura, J. Yamamoto and O. Motojima, Mechanical Behavior and Compressive Rigidity of Superconducting Coil Pack for Large Helical Device, Journal of the Cryogenic Society of Japan, Vol. 29, No. 2: 16 (1994).Google Scholar
- 6.H. Tamura, Y. Takagi, Y. Shindo, A. Nishimura, T. Mito, J. Yamamoto, O. Motojima and LHD group, Analysis of Mechanical Rigidity Simulates Superconducting Coil Pack at Low Temperature, Advances in Cryogenic Engineering 40: 1421 (1994).Google Scholar
- 7.S. Imagawa, N. Yanagi, S. Yamaguchi, T. Satow, J. Yamamoto, O. Motojima and LHD group, Construction of Helical Coil Winding Machine for LHD and On-site Winding, Proceedings of MT-14 B10 (1995).Google Scholar
- 8.Y. Tsukazaki, S. Nishijima, K. Ohta, T. Okada and K. Asano, Mechanical Properties of High-Glass-Content GFRP Laminate at Low Tempetature, Journal of the Cryogenic Society of Japan, Vol. 30, No. 4: 26 (1994).Google Scholar
- 9.R. M. Jones, “Mechanics of Composite Materials,” McGraw-Hill, New York (1975).Google Scholar