Density reduction on plasma sheath in high velocity flow field by traveling magnetic field

During sustained hypersonic flight or re-entry, the surface of the vehicle is enveloped by a plasma sheath. The high-density plasma sheath absorbs and reflects radio signals, resulting in communication blackout. The application of traveling magnetic field (TMF) to mitigate communication blackout has been proven effective. In this paper, to address the neglect of the plasma flow field in the existing TMF models, and to improve the methods of reducing the plasma density by one-dimensional TMF, a two-dimensional TMF model is proposed. The mathematical description of the two-dimensional TMF and the plasma density are derived, the distribution of the plasma density in the flow field by TMF and the temporal evolution are investigated. The density distribution results reveal that the width of the region with a 40% plasma density reduction can reach up to 0.13 m, which typically satisfies the size requirement for communication, and the results of density temporal evolution show that the plasma density reduction in this region can be maintained between 48% and 56%. Moreover, the effects of changing the plasma sheath parameter and TMF parameter on the density reduction are also considered in this study. Based on the simulation results, the mechanism of interaction between the TMF and the plasma flow field is physically analyzed. The temperature field velocity field is introduced to explain the rationality of the simulation results, further validating the feasibility of using TMF to reduce plasma density.