This paper presents the characteristics of L-mode detachment,together with the behavior of edge turbulent transport and plasma confinement on the HL-2A tokamak.Partially detached and pronounced detached states have be...This paper presents the characteristics of L-mode detachment,together with the behavior of edge turbulent transport and plasma confinement on the HL-2A tokamak.Partially detached and pronounced detached states have been achieved in L-mode plasma.Stored energy was maintained before and after detachment.Edge turbulence and its transport have increased obviously in the partially detached state.In the pronounced detached state,redistribution of the density and temperature profiles due to detachment leads to low amplitude of electron temperature and pressure,as well as very weak edge turbulence and transport.Despite strong plasma radiation in the pronounced detached state,reduced edge turbulent transport contributes to maintaining stored energy in detached L-mode plasma in HL-2A.Different detachment states play an important role in the redistribution of density and temperature profiles,which requires further study.展开更多
A newly designed divertor Langmuir probe diagnostic system has been installed in a rare closed divertor of the HL-2A tokamak and steadily operated for the study of divertor physics involved edge-localized mode mitigat...A newly designed divertor Langmuir probe diagnostic system has been installed in a rare closed divertor of the HL-2A tokamak and steadily operated for the study of divertor physics involved edge-localized mode mitigation,detachment and redistribution of heat flux,etc.Two sets of probe arrays including 274 probe tips were placed at two ports(approximately 180°separated toroidally),and the spatial and temporal resolutions of this measurement system could reach6 mm and 1μs,respectively.A novel design of the ceramic isolation ring can ensure reliable electrical insulation property between the graphite tip and the copper substrate plate where plasma impurities and the dust are deposited into the gaps for a long experimental time.Meanwhile,the condition monitoring and mode conversion between single and triple probe of the probe system could be conveniently implemented via a remote-control station.The preliminary experimental result shows that the divertor Langmuir probe system is capable of measuring the high spatiotemporal parameters involved the plasma density,electron temperature,particle flux as well as heat flux during the ELMy H-mode discharges.展开更多
基金National Key Research and Development Program of China(Nos.2018YFE0303102,2018YFE0309103,2017YFE0300405 and 2017YFE0301203)National Natural Science Foundation of China(Nos.U1867222,11875124,11905051,11805055 and 11875020)Sichuan Youth Science and Technology Innovation Team Project(No.2020JDTD0030)。
文摘This paper presents the characteristics of L-mode detachment,together with the behavior of edge turbulent transport and plasma confinement on the HL-2A tokamak.Partially detached and pronounced detached states have been achieved in L-mode plasma.Stored energy was maintained before and after detachment.Edge turbulence and its transport have increased obviously in the partially detached state.In the pronounced detached state,redistribution of the density and temperature profiles due to detachment leads to low amplitude of electron temperature and pressure,as well as very weak edge turbulence and transport.Despite strong plasma radiation in the pronounced detached state,reduced edge turbulent transport contributes to maintaining stored energy in detached L-mode plasma in HL-2A.Different detachment states play an important role in the redistribution of density and temperature profiles,which requires further study.
基金partially supported by National Natural Science Foundation of China(Nos.11875017,11875020,12175186 and 11905052)the National Magnetic Confinement Fusion Science Program of China(Nos.2019YFE03030002,2017YFE0301203 and 2018YFE0310100)the Sichuan Outstanding Youth Science Foundation(No.2020JDJQ0019)。
文摘A newly designed divertor Langmuir probe diagnostic system has been installed in a rare closed divertor of the HL-2A tokamak and steadily operated for the study of divertor physics involved edge-localized mode mitigation,detachment and redistribution of heat flux,etc.Two sets of probe arrays including 274 probe tips were placed at two ports(approximately 180°separated toroidally),and the spatial and temporal resolutions of this measurement system could reach6 mm and 1μs,respectively.A novel design of the ceramic isolation ring can ensure reliable electrical insulation property between the graphite tip and the copper substrate plate where plasma impurities and the dust are deposited into the gaps for a long experimental time.Meanwhile,the condition monitoring and mode conversion between single and triple probe of the probe system could be conveniently implemented via a remote-control station.The preliminary experimental result shows that the divertor Langmuir probe system is capable of measuring the high spatiotemporal parameters involved the plasma density,electron temperature,particle flux as well as heat flux during the ELMy H-mode discharges.