几种不同波数时的角向扰动磁场

Dependence of Evolution of Poloidal Disturbed Magnetic Field on Wave Number: A Semi-Analytical Study

数值模拟了不同波数时,等离子体粘度的角向扰动磁场的演化规律,并与理想磁流体时的角向扰动磁场进行了比较,得到的主要结论是:等离子体压强较小时,大波数对应的角向扰动磁场为正值,小波数的角向扰动磁场为负值;等离子体压强较大时,大波数对应的角向扰动磁场也有负值出现。另外,当等离子体压强一定时,随着等离子体粘度的增加,角向扰动磁场的波动幅度越大。

We semi-analytically addressed the evolution of poloidal disturbed magnetic field with plasma viscosity at different wave numbers.The influence of the wave number,plasma pressure and viscosity on the poloidal disturbed magnetic field was investigated by numerically solving the 2^(nd)-order ordinary differential equations of eigen-functions(ξ_r),derived from ideal magneto-hydrodynamics equations via Flourier transformation.The numerical calculation results show that depending on the plasma pressure,the wave number has a major impact.At a low plasma pressure,a large(a small) wave number results in a positive(a negative) poloidal disturbed magnetic field;however,at a high plasma pressure,a large wave number also corresponds to a negative disturbed magnetic field;and at a fixed plasma pressure,an increase of the plasma viscosity heightens the fluctuation amplitude of poloidal disturbed magnetic field.