高β等离子体中低混杂漂移不稳定性

HIGH BETA EFFECTS ON THE FLUTE LOWER HYBRID DRIFT INSTABILITY

本文对高β等离子体中槽纹模低杂漂移不稳定性从迴旋动力论出发作了较系统的研究,考虑了密度梯度、电子的温度梯度以及磁场梯度漂移的共振效应,解析结果与数值计算取得了完全一致的结论。发现,当温度梯度方向与密度梯度方向相反时,与温度梯度有关的电子的磁漂移共振起不稳定作用,使模的增长率比温度均匀时明显增大;而当方向相同时,温度梯度效应加强电子磁漂移共振的稳定作用,减少模的增长率。在两种情形中随着β值的增大,模的增长率都会减小,而且最大增长率向长波方向移动。电子温度各向异性对模的性质没有影响。

The high βflute lower hybrid drift (LHD) instability is studied in detail. The dispersion relation governing LHD mode with density, electron temperature inhomo-geneities and magnetic drift resonance is derived via gyrokinetic equations. It is found that when (?)Te //(?)n the magnetic drift resonance related to (?)Te, enhances the instability and when (?)Te//(?)n the resonance reduces the instability. In both cases, the finite βprovides a stability effects and shifts the largest growth rate point to the longer wave length. The analytical and numerical results are in good agreement. Electron temperature anisotropy gives no contribution to LHD mode.