Electron Cyclotron Wave Heating and Current Drive Simulation Based on Three-dimensional Fokker-Planck Equation

Abstract

Abstract: 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.

Key words: Fokker-Planck equation, distribution function, electron cyclotron wave, heating and current drive

CLC Number:

O532

ZHENG Pingwei, HE Lihua, HUANG Qianhong, DENG Sheng, GONG Xueyu. Electron Cyclotron Wave Heating and Current Drive Simulation Based on Three-dimensional Fokker-Planck Equation[J]. CHINESE JOURNAL OF COMPUTATIONAL PHYSICS, 2017, 34(4): 387-393.

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