Study Of Improvement Of H Factor And Energy Confinment In EAST Tokamak

Energy confinement time and confinement improvement factor(H factor)are the key parameters in evaluating plasma performance,can be a criteria for high confinement plasma discharges(H-mode).In this paper,the improved calculation of energy confinement time and H factor have been studied,together with analysis of the confinement of typical discharges in EAST,resulting in the form of scaling law with RF dominant heating and current drive,which can contribute for CFETR.In this paper,the absorption coefficient of Lower Hybrid Wave(LHW)with different discharge conditions is systematically studied for the first time on EAST,where the absorption coefficient of LHW decrease when the electron density increase and the absorption coefficient of LHW is higher when toroidal magnetic is higher;the absorption is better when frequency of LHW is higher.Meanwhile,the absorption coefficient scaling of LHW in different electron density,toroidal magnetic filed and different system is consistent with the simulations.In the study of Neutral Beam Injection(NBI),conditions of plasma current,electron density and different beam energy were simulated with TRASNP.The estimation formula of NBI absorption coefficient is given through regression analysis.In addition,the fast ion energy is discussed with a reasonable formula.The improved of energy confinement time and H factor allows the further analysis and form the scaling laws for ohmic mode database,L mode database and H mode database.The coefficient of elongation is-2.3,contrast to the IPB98(y,2)scalingbut similar to the KSTAR's.The coefficient of loss power is-0.59,not much lower than-0.69 in IPB98(y,2)scaling.Finally,the synergy of LHW and ECRH is existing.The higher confinement improbed by?20%is observed with ECRH,leading to a higher betaP.The confinement of He plasma is lower than that of D plasma by 30%when comparing tow discharges with the similar parameters.According to the studies of typical discharges such as high betaP and high betaN on EAST,the improved calculation of the confinement time and the H factor are consistent with those increaserd or decreased confinement from other diagnostics.