On the Possibility of Applying ECR Heating and Current Drive in the DEMO-S and DEMO-FNS Facilities.

This article presents the first results of calculations of power contribution of electron cyclotron heating power and driven current in the DEMO-S and DEMO-FNS facilities for their design parameters and model distributions of temperature, density, and effective plasma charge. The calculations were based on OGRAY code for in-axis and off-axis power contribution. It has been demonstrated that, for electron cyclotron heating and current drive in the central part of plasma thread in the DEMO-FNS, the wave sources are required to operate in the frequency range available in modern experiments: ~140–160 GHz. The off-axis power contribution in the DEMO-FNS in calculations is provided by displacement of resonance region toward the high field side. It has been shown that, in order to generate EC current at ρ ~ 0.65 in the equatorial plane at the high field side, the wave frequency should be increased to ~185 GHz. In order to heat plasma and to generate current using EC waves in the DEMO-S the EC radiation sources are required to operate in the range of 200–230 GHz. In the regimes with low plasma temperature (Te(0) < 10 keV) in both facilities, the fraction of single-pass absorption upon off-axis power contribution has been lower than 50%, which requires further optimization of the power contribution and, probably, discharge scenario. [ABSTRACT FROM AUTHOR]