Finite element stress analysis of orthotropic solenoids

The mechanical behavior of superconducting magnets deviates from isotropy due to their construction techniques, which involve the layering of superconductor, insulation, and sometimes structural reinforcement within the windings. This paper describes a finite element stress analysis which has been extended to consider the effects of orthotropic material properties, as well as differential thermal contraction and spatially varying magnetic body forces. The procedure is applicable to all arbitrarily shaped axisymmetric magnets. A comparison between the finite element stress analysis and an analytical solution for a rotationally transversely isotropic solenoid is presented. Good agreement is obtained within the limits of the analytical solution.