In the HL-2A 2004 experiment campaign, pulsed molecular beam injection (MBI) and strong hydrogen gas puffing under the divertor configuration were used for gas fueling. The experimental results show that the MBI of ...In the HL-2A 2004 experiment campaign, pulsed molecular beam injection (MBI) and strong hydrogen gas puffing under the divertor configuration were used for gas fueling. The experimental results show that the MBI of hydrogen can reduce the heat flux to the divertor target plate. The electron temperature measured by the Langmuir probe array decreases significantly during the injection of the molecular beam whereas the electron density increases. This indicates that the plasma pressure near the target plates tends to be constant at a new equilibrium level. In the divertor plasmas with strong hydrogen gas puffing a high plasma density up to 4.4 × 10^19 m^-3 was achieved. In addition, a phenomenon similar to the partially detached divertor regime was observed, which is being studied in open divertor tokamaks such as DIII-D to reduce the peak heat flux on the target plates near the separatrix. After a strong gas puffing the electron temperature measured on the outer divertor target plate near the separatrix decreases till below 5 eV or even lower, but that of the farther outer divertor target plate does not change obviously; and the CIII and the Ha emissions at the plasma edge decrease as expected, but the Ha emission near the Xpoint increases. These results reflects some interesting characteristics, which needs to be studied by further modeling and experiments.展开更多
An ion source for HL-2A Neutral Beam Injection(NBI)was operated successfully in March 2007,in South- western Institute of Physics.A bucket source type and three-grid-system are used in this new ion source design.The f...An ion source for HL-2A Neutral Beam Injection(NBI)was operated successfully in March 2007,in South- western Institute of Physics.A bucket source type and three-grid-system are used in this new ion source design.The filament current of ll00A,filament voltage of 12V,arc current of 1050A,arc voltage of 120V,highest plasmas density of 2.5×10^(12)/cm^3,extracted ion beam density of 0.44A/cm^2,plasma density uniformity better than 5% in the area close to the first grid,duration of 2s,for this new source,have been achieved.The conceptual design,mechanical design and experiment result for the ion source are presented briefly in this paper.展开更多
基金supported in part by the JSPS-CAS Core University Program in the field of Plasma and Nuclear Fusion
文摘In the HL-2A 2004 experiment campaign, pulsed molecular beam injection (MBI) and strong hydrogen gas puffing under the divertor configuration were used for gas fueling. The experimental results show that the MBI of hydrogen can reduce the heat flux to the divertor target plate. The electron temperature measured by the Langmuir probe array decreases significantly during the injection of the molecular beam whereas the electron density increases. This indicates that the plasma pressure near the target plates tends to be constant at a new equilibrium level. In the divertor plasmas with strong hydrogen gas puffing a high plasma density up to 4.4 × 10^19 m^-3 was achieved. In addition, a phenomenon similar to the partially detached divertor regime was observed, which is being studied in open divertor tokamaks such as DIII-D to reduce the peak heat flux on the target plates near the separatrix. After a strong gas puffing the electron temperature measured on the outer divertor target plate near the separatrix decreases till below 5 eV or even lower, but that of the farther outer divertor target plate does not change obviously; and the CIII and the Ha emissions at the plasma edge decrease as expected, but the Ha emission near the Xpoint increases. These results reflects some interesting characteristics, which needs to be studied by further modeling and experiments.
文摘An ion source for HL-2A Neutral Beam Injection(NBI)was operated successfully in March 2007,in South- western Institute of Physics.A bucket source type and three-grid-system are used in this new ion source design.The filament current of ll00A,filament voltage of 12V,arc current of 1050A,arc voltage of 120V,highest plasmas density of 2.5×10^(12)/cm^3,extracted ion beam density of 0.44A/cm^2,plasma density uniformity better than 5% in the area close to the first grid,duration of 2s,for this new source,have been achieved.The conceptual design,mechanical design and experiment result for the ion source are presented briefly in this paper.