Investigation of Edge Plasma Features in the HL-IM Tokamak

1.IntroductionInordertooptimizetokamakandachievehighperformanceplasmasuchashighcentraldensityandtemperature,goodcoreconfinementetc.,thesimultaneouscontroloftheedgeplasmaandcentraloneiscrucial.Therefore,themeasurementandcontroloftheedgeplajsmaparametersareverysignificanttocentralplasma.EdgeparameterssuchaStheedgedensity,temperatureandspacepotentialareusuallymeasuredbyusingLangmuirprobes.Duetotheprobemeasurementwithhightemporalandspa-tialresolution[1],itcanalsobeusedtoinvestigatetheirfluctuatio…     

Steady-State Plasmas in KT5D Magnetized Torus

Steady-state plasma generated by electron cyclotron resonance （ECR） wave in the KT5D magnetized torus was studied using a fast high-resolution camera and Langmuir probes. It was found that both the discharge patterns taken by the camera and the plasma parameters measured by the probes were very sensitive to the working gas pressure and the magnetic configuration of the torus both without and with vertical fields. There existed fast vertical motion of the plasma. Tentative discussion is presented about the observed phenomena such as the bright resonance layer at a high gas pressure and the wave absorption mechanism at a low pressure. Further explanations should be found.     

Numerical Simulation and Experimental Identification of Divertor Configuration in the HL-2A Tokamak

Single- and double-null divertor configurations in HL-2A are simulated by SWEQU equilibrium code. Lower divertor discharges in the first physics campaign have been achieved by two kinds of power supply method of multipole-field coils. Single-null divertor configuration has been identified by visible photography, target probe arrays and the reconstructed magnetic surface. Magnetic separatrix and minor radius of plasma column are obtained by a reconstructed code of multiple current filaments using 18 Mirnov signals.     

High Density Experiments in the HL-1M Tokamak

1.IntroductionHighdensityoperationisveryimportantforeconomicfusionreactor.ffesearchershavealwaysfoundadensitylicitinatokamak.Disruptionwilltakeplacebeyondthelimit.Themaximumdensityisfounddifferent,dependingonmachinesandoperationconditions.Therefore,theinvestigationOfhighdensityanditsdisruptioncontrolisveryimportantinfuturefusionreactors.UPto"owltherearequiteanumberofproposalsfordensitylimit.ThefirstwasoutlinedbyMurakandin1976[l].Itsmaximumlineaverageddensity(n.)isproportionaltotheratioofthe…     

HL-1M装置边缘等离子体特性研究

边缘和芯部等离子体的同时控制对优化托卡马克等离子体性能是重要的。边缘等离子体密度、温度和空间电位等通常采用朗缪尔静电探针测量,而旋转速度可用马赫探针测量。好的加料技术对于获得高性能等离子体也很重要,在HL-1M装置上已开展了8发弹丸注入和分子束注入(MBI)加料实验,它能使等离子体产生中空的温度和电流密度分布,并容易获得高密度和良好的约束。本文主要介绍在低杂波电流驱动(LHCD)、多发弹丸注入和MBI三种典型放电中边缘等离子体参数的测量结果。     

HL-1M装置锁模不稳定性研究

在大型托卡马克装置中,各种线圈安装的微小偏差将会引起严重的误差场不稳定性,导致锁模类大破裂,因此,锁模不稳定性是研究误差场不稳定性的基础。本文分析了HL-1M装置锁模不稳定性的产生条件及其特点,并提出抑制锁模不稳定性的参考建议。     

A brief review: experimental investigation of zonal flows and geodesic acoustic modes in fusion plasmas

Zonal flows self-generated by turbulence play an important role in regulating turbulence, reducing transport level, and thus improve plasma confinement in fusion plasmas. The zonal flows and geodesic acoustic modes have been identified in various devices. The related issues, such as the poloidal and toroidal symmetries, coupling to turbulence, effects on turbulence and transport, nonlinear energy transfer between turbulence and zonal flows, dependence of the plasma parameters, roles in the confinement regime transitions etc are overviewed briefly in this paper. The interaction between zonal flows and magnetic islands is emphasized.     

HL-1M装置离子回旋波注入实验的边缘参数测量

为了提高等离子体温度和密度,在高参数下从事托卡马克等离子体物理研究,在HL-1M装置上进行低杂波加热和电子回旋波加热的基础上,我们最近开展了离子回旋波注入和中性束注入加热实验,以及弹丸注入加料和分子束注入(MBI)加料实验,特别是在后者的实验中获得了很高的粒子和能量约束时间。