Driven current profile and absorbed power profile are obtained with three-dimensional bounce-averaged Fokker-Planck equation in the presence of electron cyclotron wave. An additional term relate to radial transport is added to the equation accounting for influence of super-thermal electrons radial diffusion for current drive. Coefficient matrix is got by discretizing Fokker-Planck equation using nine-point center differential scheme. Incomplete LU decomposition is executed for precondition purpose. Making use of BiCGSTAB method, distribution function is calculated numerically, from which the drive current profile and absorbed power of electron cyclotron wave is calculated without radial transport. Driven current profile is compared with that of BANDIT3D with radial transport considered. It is shown that tendency of our result matched well with BANDIT3D.

With given total toroidal current and central current density of plasma, temperature, density and magnetic field profiles of tokamak plasma with different elongation and triangularity are obtained numerically with Grad-Shafranov equation. Electron cyclotron wave ray trajectories and current drive in configurations are investigated with Fokker-Planck equation incorporated into a ray tracing code. It shows that as electron cyclotron wave of X-mode are launched from top, rays propagate toward low-field side with increasing elongation. As electron cyclotron wave are launched from mid-plane and low-field-side, high quotient power deposition is obtained with greater elongation, and driven current profile is close to central plasma with increase of triangularity. Current drive profile moves toward central plasma and peak current density increases with decreasing poloidal or toroidal injection angle.

Heating of magnetized plasma through one towards mutiple shear Alfvén waves with low frequency propagating along background magnetic field is studied with test particle simulation.It shows that mutiple waves whose frequencies match resonance condition lead to significantly efficiency heating by strengthen non-resononce process. With evolution of heating, mutiple waves turn to modulation wave. As frequencis of mutiple waves are close wave packets are created in transverse direction. A great ion temperature anisotrophy is produced and after that randomization process is stengthened either. Efficiency of stochastic heating process is also enhanced.It can be used in controling non-resonance and stochastic heating process by changing frequencise of mutiple low frequency waves.

Effects of external current drive on instability of double tearing mode in Hall MHD equations are numerically investigated. It shows that double tearing mode can be suppressed by antiparallel external current drive at x-point of tearing mode magnetic islands. Periodic external current drive controls island width under a threshold and stabilizes double tearing mode. With increasing period depression effect becomes worse. If frequency, density and width of periodic external current drive are adopted suitably, depression effect becomes better.

Heating of magnetized plasmas by low-frequency Alfvén waves propagating along background magnetic field is studied with test particle simulation.It shows that ions in perpendicular and parallel directions of the background magnetic field are heated significantly.In a stage of non-resonance heating,perpendicular heating is more significant than parallel heating,and anisotropic temperature comes into being.In a stage of stochastic heating,perpendicular and parallel temperatures of ions finally reach saturation and convergence.In heating process,the maximum kinetic temperature of ions is dependent on the ratio of magnetic field energy density and plasma density,which has no relevance with Alfvön-wave frequency and amplitude.Ions are significantly accelerated in parallel direction.and attained a bulk speed that is roughly equal to phase velocity of Alfvén waves.

With a hypothesis that energy is completely absorbed by plasma in a plasma slab model and a three-dimensional antenna model,we numerically stimulate coupling of two strip antennas with plasma in ion cyclotron resonance heating.Antenna radiation power and power density distribution absorbed by plasma at different antenna distances are calculated.Through analyzing we draw a conclusion: For two strip antennas feed in phase at certain experimental parameters,the shorter the antenna distance is,the better ion cyclotron resonance heating is.

A full wave numerical method is developed for fast wave current drive in tokamak plasmas,in which finite Larmor radius effects and parallel dispersion are taken into account.A physical model with full wave are developed.Electric field distribution in radial is obtained.It shows that fast wave can propagate to central plasma;Mode conversion happened near central plasmas;Fast wave can drive current in centre to improve balance current profile;Parallel electric is weaker than that in vertical direction.The current is droven by Landau damping and transit-time magnetic pumping.

Shear flows in resonant surfaces of Tokamka devices induced by nonhnear evolution of double tearing modes(DTM) are studied numerically in the framework of resistive magnetohydronamic model with slab geometry.It is found that in early phases of nonlinear evolution of DTM,no remarkable shear flows is generated in resonant surfaces.Effective shear flows emerge during the phase of fast magnetic reconnection and disappear finally.Both amplitude and distribution of shear flows are found vary with nonlinear evolution of magnetic islands.Moreover,by taking into account plasma resistivity,it is shown that greater plasmas resistivity results in faster magnetic reeonection, but it hardly affects shear flows of resonant surfaces in Tokamka devices.