Numerical Studies on Mechanical Behavior of Dry-Wound HTS Racetrack Coil

Abstract

This paper presents numerical studies on the mechanical behavior of dry-wound high-temperature superconducting (HTS) racetrack coil. After calculating the Lorentz force induced from the self-field of the racetrack coil based on the 3D finite element method (FEM), the 2D mechanical stress analysis is performed based on the plane-stress assumptions to mitigate computational loads, and the mechanical behavior including displacement and stress are investigated. Based on analysis model, two following case studies are conducted: 1) analysis of mechanical behavior on various-shaped of racetrack coils having a different ratio of straight section length and semicircular section radius, and 2) analysis of stress reduction effect according to the degree of curvature when slight curvature is included in the straight section. In each case study, the factors affecting the mechanical behavior of racetrack coils are numerically analyzed and their trends are presented. The results obtained in this paper would be useful for the design of dry-wound racetrack coil, including no-insulation coil, applied in a large-scale and high-field application.