Study On Alfven Eigenmode

Alfven eigenmodes (AEs) is one of the hot and crucial issues in plasma physics. Inside the Alfven Continua Gaps of different frequencies, a variety of AEs can reside such as toroidicity-induced Alfven eigenmodes(TAEs), beta-induced Alfven eigenmodes(BAEs).The first RSAEs(Reversed Shear Alfven Eigenmodes) was observed in JT-60U Tokamak (Kimura et al.,1998), where some frequency up-sweeping modes appear near the location of re-versed magnetic shear. Later, similar phenomena were reported in the Joint European Torus (JET) and other major Tokamak devices. Most theories of RS AEs are based on ideal MHD model, which has now been extended to include various effects. Energetic Particle, Alfven Ion Temperature Gra-dient, second harmonic can excite the RSAEs. There are many researches on linear property of RSAEs while non-linear simulation of RSAEs is not widely implemented. For example, HMGC Code has been used to study the enhancement of transport of energetic particle. Comparing to TAEs or BAEs, the gyrokinetic simulations of RSAEs are still lacking.In this thesis, the KAEC code is modified to deal with Tokamak of non-circular geometry and calculate the TAEs and RSAEs eigenfunctions.The main results obtained are:enlargement of elongation makes the TAEs/RSAEs eigenvalues decrease while the following modes increase, and the enlargement of triangulation increases the eigenfrequencies of TAEs/RSAEs; when applying to experiments, the NAEs are found on an EAST-like experimental profiles, and the elongation decreases the RASEs damping at a given ion finite larmor radius on DIII-D experimental profiles.