Thermal and Modal Simulations for the CLIC Module

The accelerating technologies used in CLIC currently have an RF efficiency of about 40 % The RF losses are dissipated as heat into the cavity disks of the super-accelerating structures, which leads to unwanted thermal deformation. A water-based cooling system is employed to evacuate the excess heat and to limit the unwanted deformation. The current study analyses the influence of the cooling channel placement and layout on the cooling performance for the RF losses occurring in the drive-beam-based design and the klystron based design. All of the considered layouts extract 97.4 % of the dissipated heat. The two symmetric paths layout performs best as it results in the evenest temperature distribution and subsequent deformation. The deformation is also minimised by placing the cooling channels inside the cavity disks as close to the irises as possible. Additional pressure head loss calculations show that the pipe pressure losses are small.