Rehman Umer, Ali Ahmad, Mahmood Shakeel
Department of Physics, Air University, E-09 Complex, Islamabad, 44000, Pakistan.
National Tokamak Fusion Program, Islamabad, 44000, Pakistan.
Heliyon. 2021 Sep 20;7(9):e08020. doi: 10.1016/j.heliyon.2021.e08020. eCollection 2021 Sep.
Drift wave instabilities (DWI) associated with the two-fluid dynamics seems to be responsible for anomalous transport in modern day tokamaks. Ballooning instabilities tend to exchange flux tubes of different pressure, resulting in convective transport. The micro-level turbulence (drift wave) is coupled with the macro-level (ballooning mode) dynamics in fusion experiments. The co-existence of DWI and drift ballooning instabilities (DBI) is discussed in this work using a four-field plasma model. The formulation preserves both the microscopic and macroscopic dynamics of plasma. To demonstrate the coupling, a new dispersion relation is derived to analyze stability of the coupled modes in a non-uniform magnetized plasma. Linear stability of coupled drift-ballooning and drift-acoustic modes have been explored. The two-fluid effect (micro-level influence) through diamagnetic drift frequency for electrons and curvature drift frequency on unstable modes are demonstrated.
与双流体动力学相关的漂移波不稳定性（DWI）似乎是现代托卡马克中反常输运的原因。气球模不稳定性倾向于交换不同压力的通量管，从而导致对流输运。在聚变实验中，微观层面的湍流（漂移波）与宏观层面（气球模）的动力学相互耦合。本文使用四场等离子体模型讨论了DWI和漂移气球模不稳定性（DBI）的共存。该公式保留了等离子体的微观和宏观动力学。为了证明这种耦合，推导了一个新的色散关系来分析非均匀磁化等离子体中耦合模的稳定性。研究了耦合漂移 - 气球模和漂移 - 声模的线性稳定性。通过电子的抗磁漂移频率和曲率漂移频率对不稳定模的双流体效应（微观层面的影响）得到了证明。
