Preconceptual Design of the Port Cell Section for the EU DEMO Equatorial EC System

The EU demonstration power plant (DEMO) Tokamak will be equipped with an electron cyclotron (EC) system for plasma heating and magnetohydrodynamic (MHD) control. Up to six launchers will be installed into equatorial ports with the aim to inject maximum 130-MW millimeter-wave (mm-wave) power at dedicated positions into the plasma. The mm-waves will be generated in gyrotrons placed in a distinct building at distant location. From this gyrotron hall, a combined transmission line (TL) system of quasi-optical multibeam mirrors and individual waveguides (WGs) will propagate the mm-waves into the tokamak building. That followed, an optical system, composed of miter bends, diamond windows, valves, and microwave bellows, connects the TL through the gallery and the port cell with the EC launchers. This article presents the preconceptual computer-aided design (CAD) of this latter section of the EC system. Based on its general scheme and the given WG trajectories, the model takes into account the available space in the port cell with respect to required clearance for supply systems, assembly, and maintenance. At the preconceptual state, the design includes CAD models of all relevant mm-wave components in realistic dimensions at a level of details, appropriate to demonstrate the feasibility of the concept.