Multiscale hydraulic modeling of the ITER TF he inlets during nominal and off-normal operation

In ITER, the supercritical helium (SHe) coolant enters the superconducting toroidal field (TF) coils from the bore of the magnet, with each inlet feeding two adjacent pancakes. Here, as a complement to and extension of experimental measurements performed by other authors, we address the issue numerically through a 3-D computational fluid dynamic ("micro-scale") study of an ITER TF inlet, in both nominal and backflow conditions (e.g., in the case of a quench of the coil). The localized pressure drop at the inlet turns out to be relatively small. Nevertheless, for demonstration purposes of the multiscale approach, suitable correlations for the localized pressure drop are derived and then implemented in a lumped parameter component, to be used in the 4C system code for the "macroscale" analysis of the entire TF coil and related cryogenic cooling loops.