3D simulation of temperature, electric field and current density evolution in superconducting components

A simulation program for coupled simulation of temperature, electric field and current densities within conducting and superconducting components has been developed on the basis of a transient thermal three-dimensional finite element (3D-FE) code. In the case of superconductors, the non-linear E ( j ) characteristics of the Bi 2 Sr 2 CaCu 2 O 8 ('2212') and YBa 2 Cu 3 O 7 ('123') systems have been considered. Cooling by liquid nitrogen ('LN 2 ') was implemented as a boundary condition with a heat transfer coefficient varying according to the different boiling states. Simulations of the quench behaviour, on the influence of contact resistivities between normal- and superconducting materials and on the geometrical layout/materials selection of 3D superconducting components are presented. Eventually, the simulations are directly compared with experimental data being obtained during tests on component level. All simulations have been performed within a 10 MW resistive fault current limiter project ('CURL 10', Consortium) headed by ACCEL Instruments, Germany.