Experimental Study On The Effect Of Radial Electric Field On Transport Via Charge Exchange Recombination Spectroscopy On The EAST

The Radial Electric Field has been found to play an important role in the confinement and transport of magnetic confinement plasma.The inherent cpmplexity makes it difficult to completely study.Especially,on the high confinement modes(H-mode)and Internal Transport Barrier(ITB),it is still unclear but vital important to the behavior the Radial Electric Field in the edge and core plasma.Based on the Charge-Exchange Recombination Spectroscopy(CXRS)diagnostic,we try to study the physics of radial electric field in EAST tokamak.A Charge-Exchange Recombination Spectroscopy(CXRS)diagnostic has been installed on EAST tokamak to study the Radial Electric Field in plasma.A spectral model was developed to computate the emission spectral lines in order to develop a fitting algorithm.The passive emission lines emitted from these impurities appear in the wavelength ranged from 528 nm to 530 nm,e.g.the passive Fe lines could be recorded by eCXRS diagnostic due to the eCXRS sightlines ending on the stainless steel antenna.These lines could not be effectively removed via background subtraction.The passive lines are now typically taken out by the fitting algorithm.After the spectral line fitting and careful identification of the charge exchange component,the calculated Doppler broadening and shifts of the spectral line profile yield information on the ion temperature and rotation.In the experiment,we also observed the plume effect by beam modulation,and found that the plume effect has a certain influence on the CXRS spectrca analysis,which needs to be fitting and deducted.Zeeman effect are also studied on this thesis.After deducting the structure effects of Zeeman,we also found that deducting these effects,the accuracy of CXRS could not be improved.High-confinement mode(H-mode)is the baseline scenario for ITER operation.However,L-H transition is a mystery in magnetic confinement fusion study since 1982 when the first H-mode was found.The main objectives of this work was to use the acquired impurity density(by simulation),temperature and rotation profiles to investigate plasma transport behavior and infer the radial electric field E,from plasma force balance equation.The focus here was placed on the region of the Edge Transport Barrier(ETB)and Internal Transport Barrier(ITB).The radial electric field is readily calculated in the region of the ITB foot using measured C5+ profiles.The edge toroidal rotation plays an important role on the formation of ETB.In addition,L-H ransition and H-L transition under magnetic perturbations and density disturbance are also analyzed in this paper.It is found that RMP input and SMBI injection will change the radial electric field structure in the edge region,and then trigger the L-H transition or H-L transition.It is also found that the toroidal rotation near the edge plasma has an effect on the ELM behavior.The high toroidal rotation and shear affect the stability of the boundary localized peeling-balloon mode,and then affect the ELM behavior.E × B velocity shearing turbulence stabilization are believed to play an important role in the physics of the ITB formation on EAST high betaN discharge.Gyrokinetic stability analysis demonstrated that shearing rate ?E×B prevails over the linear Ion Temperature Gradient(ITG)growth rates ?max in the region where ITB forms.Energy Particles problem,such as fishbones,are also studied on this thesis.It is found that the turbulent transport can also be considered to be suppressed when the growth rate of the J × B force driven by the high-energy particle is equivalent to that of the ion temperature gradient mode,which can also be considered as another mechanism for the formation of the internal transport barrier.