Preliminary design and neutronic analyses of ECRH equatorial launcher toward CFEDR

Electron Cyclotron Resonance Heating (ECRH) is one of the most important heating systems to maintain long pulse and high-power steady-state operation of fusion reactors. In the recent progress of the ECRH system for the China Fusion Engineering Demonstrator Reactor (CFEDR), the launcher must adopt a modular design while maintaining total mass below the limit for remote handling (RH) maintenance requirements. A drawer-type launcher in the fusion reactor environment has been designed. The equatorial launcher (EL) is composed of two main parts: shielding unit and optical unit containing drawer-type millimeter-wave transmission components. These units form a unified port plug structure. The nuclear analysis of the EL based on the preliminary design has been completed. While satisfying radiation shielding requirements, the optimal thickness of shielding components within the drawer is computationally determined to minimize the launcher's total mass. A double labyrinth shielding configuration is implemented at the gap between launcher and vacuum vessel, with simulation results demonstrating effective suppression of neutron streaming along the gap toward the rear launcher section. The radiation damage to various launcher components is quantified to provide critical data for the structural design and lifetime evaluation. • A modular drawer-type structure launcher for researching key technologies in the fusion reactor environment is designed. • 3D neutronic model of ECRH was built to deliver the nuclear analysis. • A double labyrinth shielding configuration is implemented at the gap between launcher and vacuum vessel. • Irradiation of VV and TFC can meet the requirements after shielding optimization.