Simulation of Strain in ReBCO Tapes Under Combined Helical-Hard-Way Bending and Critical Current Measurements

Abstract

In this study, we investigate the mechanical behavior of high-temperature superconducting tapes under combined helical-hard-way bending load. The combined bending scenario is related to a helically wound solenoid where hard-way bending arises due to the connection of the tapes to the current terminals. Similar phenomena can also occur in double pancake coils due to the layer transitions. We have sought simulation methods to assess the associated mechanical strain that may lead to critical current degradation. Experimental measurements involve winding SuperOx 2G ReBCO tapes around formers with varying radii and lead angles to assess the critical current degradation resulting from combined helical-hard-way. The experimental procedure, results, and the utilized ANSYS finite element modeling approaches are presented. The strain distribution across different modeling assumptions is compared, including 2D and 3D tape models, homogenized tape material properties, and simulations accounting all tape layers individually. We evaluated the pros and cons of the presented approaches which are expected to be useful for future detailed analysis of such scenarios.