Comparison Between Results of Quench Simulation and Tests of a 13 T REBCO Coil in a Strong Background Magnetic Field

In the framework of the 40 T all-superconducting magnet project at the National High Magnetic Field laboratory, improvements have been made in a quench model and the quench code that has been constructed to simulate the behavior of a magnet consisting of an HTS inner coil set with an LTS background field. The quench model, initially developed for the NHMFL 32 T magnet project, incorporates additional details of the REBCO conductor on a localized level. These include nonuniform magnetic field distribution across each conductor turn and deformation of the turns due to screening currents which affects the true field angle applied to the conductor's a-b plane. Detailed measurements of the test coil's conductors have also been made to improve the simulations. These include the slope of the a-b plane using X-ray techniques and
I_C (B, θ, T)
of each conductor length using torque magnetometry. The test coil generating a field up to 13 T is an insulated, two-in-hand REBCO coil with twelve modules. Deliberate quench tests were performed with it in self-field and with a 11.4 T background field. The results and discussion of the comparisons are presented.