Three-Dimensional Calculation Analysis of ICRF Heating in LHD

Ion cyclotron range of frequencies (ICRF) heating is one of the heating methods for the fusion plasma experi-ments and also effective for the helical plasmas. For the purpose of analysis of the ICRF heating in the helical plasmas, the three-dimensional full-wave code has been developed. The feature of the helical system compared with the toka-mak device is the strong coupling of the toroidal harmonic modes. They cannot be treated independently. Dependence of the power absorption on the position of the ion cyclotron resonance layer is calculated including all toroidal modes. Strong power absorption was obtained when the position of the resonance layer is slightly different from the experi-mental results. Difference of the position of the resonance layer in different toroidal angle is thought to be important to achieve the good heating efficiency in the ICRF heating for the helical plasmas. Keywords: ICRF heating, helical device, full-wave code, TASK/WM, three-dimensional calculation The radio-frequency waves in the ion cyclotron range of frequencies (ICRF) have been used for the plasma heating in the magnetically confined plasmas for many years. In the hel-ical device, it was theoretically predicted that the high-energ