An Advanced Computational Approach for Evaluating Screening-Current-Induced Strain in REBCO HTS Coils Considering Electromagnetic-Mechanical Coupling

Challenges associated with screening current-induced mechanical behaviors have been identified as an essential issue that jeopardize the stable operation of coils, especially in environments with high magnetic fields. In this study, we have developed and subsequently scrutinized an electromagnetic-mechanical coupling model through numerical simulations, employing both the J-model and the finite element method. The calculation of Lorentz force, based on J-model, significantly influences on the deformation of superconducting tapes. Subsequently, the deformed geometry is iteratively fed back to the J-model for recalculating the Lorentz force. This iterative process comprehensively considers the coupling behavior. Simulation results presented in this study have been compared to the performance of a single pancake rare-earth barium-copper-oxide (REBCO) insert coil, comprising 40 turns and operating in a 12 T low temperature superconducting background field magnet. Our findings indicate that the coupled model offers a more precise correspondence with experimental data in comparison to the conventional sequential model. These outcomes carry substantial utility in enhancing the analysis of high-field REBCO magnets, thereby contributing to their improved performance and stability during operation.