Development of modelling tools for thermo-hydraulic analyses and design of JT-60SA TF coils

Abstract In the framework of the JT-60SA project, the Toroidal Field (TF) coils design has required to address reliably the choice between multiple design options and to calculate the temperature margin criterion for the superconductor. For this purpose, a tool was developed in two stages, interfacing the ANSYS code, used to model the thermal diffusion between the casing and the winding pack, with the GANDALF code which solves the 1D thermo-hydraulics inside each conductor. The first version of this Thermo-hydraulic EXtended TOol (TEXTO) was developed for producing conservative results and has allowed to simulate the fast discharge of the magnet, providing valuable results such as the mass flow expelled from each pancake. In the second stage, the ANSYS code was configured for modelling the helium transport in the casing and in the winding pack, thus computing more realistic transverse heat fluxes to be injected into the GANDALF code for an accurate calculation of the temperature margin. This second version of TEXTO, which integrates the TACOS (Thermo-hydraulic Ansys COmputation Semi 3D) module, has been used for studying the feasibility of positioning the helium inlets in the electrical connections. The temperature margin has then been found close but below the criterion of 1 K.