麦克斯韦分子碰撞下的离子分布函数及其非相干散射谱的计算

The Ion Distribution Function From Maxwell Molecule Collision Model and Calculations of Incoherent Scatter Spectra

采用麦克斯韦分子碰撞模型描述玻耳兹曼方程的碰撞项,基于双麦克斯韦分布函数得到的输运方程包含了粘滞和热流的影响,通过求解输运方程得到了离子漂移速度,平行和垂直磁场的离子温度,应力张量以及平行和垂直能量的热流矢量的表达式.进而得到了麦克斯韦分子碰撞模型下离子分布函数的16矩近似.利用非相干散射理论,计算得到了非相干散射谱.相对于简单的驰豫碰撞模型,麦克斯韦分子碰撞模型能更准确地描述非麦克斯韦分布的电离层E层的碰撞过程.

With regard to anisotropic plasmas, the Maxwell molecule collision model is used to describe ion-neutral collisions of Boltzmann equation. The viscous and heat flow are included in transport equations based on the two-Maxwellian distribution. The expressions of the ion drift velocity, ion parallel and perpendicular temperature, stress tensor and heat flow for parallel and perpendicular energy can be obtained by solving the transport equations. The ion velocity distribution of Maxwell molecule collision model can be obtained using the 16-moment approximation. According to the Sheffield＇s theories, the incoherent scatter spectra are calculated. In comparison to relaxation collision model, it is reasonable to use the Maxwell molecule collision model to describe the collision process of the non-Maxwellian ionospheric plasma in E region.