  The Conductor on Rounded Core (CORC) cables manufactured by Advanced
Conductor Technologies with current densities beyond 300 Amm^-2 at 4.2 K, and
bending diameter of up to 3.5 cm, are considered as one of the strongest
candidates for the next generation of high field power applications and
magnets. In this paper, we present a full 3D FEM model for their monolayer and
bilayer CORC cables made with up to three and six superconducting tapes
respectively, disclosing the full curve of AC losses for the monolayer cable at
magnetic fields beyond 60 mT, and the actual distribution of current density
along and across the thickness of the superconducting tapes in both designs.
The model is based on the so-called H-formulation, allowing to incorporate the
true three-dimensionality of the tapes without recurring to 2D thin-film
approaches where non-physical surface currents that do not follow the
celebrated Bean's model for type-II superconductors appear. Likewise, good
agreement with the experimentally measured AC-losses for the monolayer and
bilayer cable have been obtained, with all the details of the model disclosed
in this paper.
