The design of a slit ICRF antenna in EU-DEMO

Although ICRF heating has achieved the high heating efficiency necessary to achieve high-performance plasmas, it has not overcome the reliability and economic problems associated with the antenna structure inside the vacuum vessel in fusion reactors. We suggested a slit ICRF antenna that uses the blanket surface as a transmission line to solve these problems. With a single slit ICRF antenna with a width of 3 m and a height of 15 cm, the electric field strength to the magnetic field direction was successfully suppressed to 5 kV/cm when 20 MW of power radiation was achieved from the single slit. The slit ICRF antenna had a bending angle in the electromagnetic wave transmission path to prevent direct neutron impact on the first wall and a vacuum gate from rapidly preventing water or air leakage accidents. The slit ICRF antenna has a simple structure that allows heating at high power density while minimizing blanket volume reduction.