三维行波磁场对等离子体鞘套密度的调控作用  

Effect of three-dimensional traveling wave magnetic field on plasma sheath density

作　　者：徐子原 周辉 刘光翰 高中亮 丁丽 雷凡 Xu Zi-Yuan;Zhou Hui;Liu Guang-Han;Gao Zhong-Liang;Ding Li;Lei Fan(School of Electrical and Electronic Engineering,Shandong University of Technology,Zibo 255000,China;School of Electrical and Control Engineering,Shaanxi University of Science and Technology,Xi’an 710016,China)

机构地区：[1]山东理工大学电气与电子工程学院,淄博255000 [2]陕西科技大学电气与控制工程学院,西安710016

出　　处：《物理学报》2024年第17期225-239,共15页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:62101310,62304125);陕西省青年自然科学基金(批准号:2023-JC-QN-0051)资助的课题.

摘　　要：飞行器以高超音速飞行或再入过程中,表面会被等离子体鞘套包覆.等离子体鞘套会阻碍电磁波传播,造成飞行器无线电信号衰减甚至中断,即通信黑障.行波磁场是一种能够通过调控等离子体鞘套密度来缓解通信黑障的磁场.本文针对一维行波磁场无法准确描述空间内等离子体密度分布的问题,建立了三维行波磁场产生模型和三维等离子体密度分布模型.通过研究行波磁场与等离子体相互作用的机理,得到了空间内等离子体的密度分布.研究结果表明,在行波磁场的作用下,等离子体会往飞行器前端汇聚,从而在后端形成尺寸为50×100 mm的密度降低区域,使该区域内的等离子体密度最大降低71%,且提供持续的通信时间.基于RAM-C飞行试验的数据,利用所提出的模型研究了电流大小和行波速度对飞行器再入过程中电磁波衰减的影响,同时对比了行波磁场与外加静磁场对电磁波衰减的抑制效果.结果表明,施加行波磁场能够使飞行器在30.48 km处的X波段以及其他高度处的L波段、S波段、C波段和X波段的电磁波衰减降低到30 dB以下.行波磁场和静磁场的对比结果表明,行波磁场对电磁波衰减的抑制效果明显优于静磁场.When the vehicle travels at a hypersonic speed or during re-entry,the surface is covered by a plasma sheath.Plasma sheath can impede electromagnetic wave propagation,causing vehicle radio signals to be attenuated or even interrupted,which is communication blackout.The traveling magnetic field is a kind of magnetic field that can mitigate the communication blackout by adjusting the density of the plasma sheath.In this work,a three-dimensional traveling magnetic field generation model and a three-dimensional plasma density distribution model are established for the problem that the one-dimensional traveling magnetic field cannot accurately describe the plasma density distribution in space.The mechanism of the interaction between the traveling magnetic field and the plasma is investigated to obtain the plasma density distribution in space.The results show that applying a traveling magnetic field can generate a density reduction region of 50×100 mm at the rear of the vehicle,resulting in a maximum decrease of 71%in plasma density in the region and providing continuous communication time.Meanwhile,the effects of initial density,collision frequency,traveling velocity and current magnitude on the plasma density distribution are investigated.The results show that with the increase of the initial density,the ability to regulate the plasma density is improved.However,due to the large density base,the adjusted plasma density is still higher than the plasma density of the low-density case.The increase of the collision frequency can significantly reduce the regulation effect.Increasing the traveling velocity and current can enhance the density-adjusting effect.However,further increasing the traveling velocity to above 800 m/s does not yield a more significant adjustment effect.Based on the data from the RAM-C flight test,the proposed model is used to study the effects of current magnitude and traveling velocity on the electromagnetic wave attenuation during aircraft reentry.The mitigation effect of the traveling magnetic fie

关 键 词：等离子体鞘套 通信黑障 行波磁场 密度调控 

分 类 号：O539[理学—等离子体物理] V419[理学—物理] V556[航空宇航科学与技术—航空宇航推进理论与工程]