Comare with the result of gyro-kinetic code and particle code

• Main Authors: Chuan-Kai Lyu, 呂傳楷
• Other Authors: Wei-Hsiung Tsai
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/49073683098870104806

碩士 === 國立中央大學 === 太空科學研究所 === 90 === In the past simulation, particle code consistent many scale physical phenomenon, but these are mixed. When aiming at large scale, low frequency phenomenon, it can’t be recognized from simulation result. Gyro-kinetic simulation can filtered small scale, high frequency waves by average the gyro-phase angle, so it can be used in studying the low frequency wave. The main method is to solve Vlasov-Poisson equation, which different from Vlasov equation is moved out the phase angle. Vlasov-Poisson equation averaged the phase angle, and can vanish the gyro-effect from equation of motion. Because of eliminating the gyro-effect, the simulation can use larger time step（WH*Dt<=1）and larger grid（Dx/zo(s)<=1）,where the electrostatic shear-Alfven wave frequency WH is much smaller then the plasma frequency Wpe. Using larger time step and larger grid can reduce the total computer time. The following is used the new numerical method to construct gyro-kinetic code, and compared its result with particle code simulation result. Its comparison shows the advantage the previous discussed.