Validation of Alfven Eigenmodes Stability Using Multiple Codes and Projection for CFETR Operation

Alfven Eigenmodes (AEs) are driven by on-axis injected neutral beam (NB) in DIII-D #166496 and #159243 discharges, which are validated by NOVA-K and TGLFEP codes. A good agreement between two codes shows low-n (n=1~2) Toroidal Alfven Eigenmodes (TAEs) and low-n (n=2~6) Reversed Shear Alfven Eigenmodes (RSAEs) are unstable in two discharges, respectively. Two codes are also employed to predict linear AEs stability destabilized by α particle in China Fusion Engineering Test Reactor (CFETR) phase1 scenario. The growth rate of AEs change periodically with toroidal mode number increasing and the RSAEs near the rational surface always have larger growth rate than TAEs. Further the AEs are destabilized by adding 500keV off-axis injected NB. Fitting method of EFIT is applied to construct a set of equilibria with different q_min and magnetic shear to investigate the impact of q-profile on AEs stability for CFETR phase1 scenario. The results show that high and rational q_min can destabilize RSAE stability, which can be stabilized by strong shear. Besides, increasing plasma density is benefit for AEs stability by raising electron collision damping.