Magneto-Mechanical Coupling Analysis of a Superconducting Solenoid Using FEM With Different Approaches

The high-field superconducting magnet carrying with high current density are commonly exposed to large Lorentz forces leading to the unavoidable deformation in superconducting coils. The deformation will further disturb the magnetic field quality and the operating safety and stability of the magnet. An accurate estimation of the magneto-mechanical behaviors during excitation of superconducting coils is a crucial one. In this paper, the magneto-mechanical characteristics and behaviors of a 10 T superconducting solenoid were analyzed using the coupled finite element modeling (FEM). Three different approaches were developed, which include the isotropic homogenized modeling based on the mixture rule of composites, the orthotropic homogenized modeling based on the representative volume element (RVE) method, and the hierarchical modeling with multilevel details. The simulations show that the FEM predictions on magneto-mechanical behaviors of the superconducting coils using the hierarchical model are in better agreement with the experimental data compared to the isotropic and orthotropic homogenized models. The orthotropic homogenized modeling gave good predictions on the mechanical characteristics of superconducting solenoid. More fine strain/stress profiles of the superconducting wire, wire insulation and filling material have been obtained by the hierarchical modeling, which are vital for evaluation of mechanical properties of the interface among superconducting coils and the matrix, as well the inclusions.