Simple Core-SOL-Divertor Model To Investigate Plasma Operational SpaceR.Hiwataria, Y.Kuzuyamab, A.Hatayamab, K.Okanoa, Y.Asaokaa, S.Zhuc, and Y.TomitadaCentral Research Institute of Electric Power Industry(CRIEPI), Tokyo 201-8511, JAPANb

Faculty of Science and Technology, Keio University, Yokohama 223-8522,JAPANc

Institute of Plasma Physics, Chinese Academy of Sciences, Hefei, P.R.China
dNational Institute for Fusion Science, Toki 509-5292, JAPANTo understand operational SOL-Divertor conditions is the critical issue to realize a fusion power plant.
Those conditions should be investigated consistently with core plasma conditions. Recently, the core plasma
performance required to generate net electric power is roughly revealed [1]. According to that study, we have toincrease the ratio of greenwald density limit (fnGW) together with normalized beta value (βN), and fnGW required
to generate net electric power depends on the core plasma temperature. The core plasma temperature will berestricted by the divertor operation of detateched plasma. Consequently, the relationship between the coreplasma temperature and the divertor operation condition has a great impact on fnGW required for a fusion power
plant. To understand such relationship between core and SOL-divertor plasma, we integrated 0D core plasma
model and two-point model into a simple Core-SOL-Divertor (C-S-D) model.
The 0D core plasma model is based on ITER physics design guideline [3] and the LH transiton condition is
installed by the same fashion as in ref. [4]. The two-point model[5,6] is basically applied to SOL-divertor
analysis. The SOL density, which is usually a given parameter, has to be calculated including the core plasma
conditions such as particle and heat flux across the separatrix. In the present study, we solve the particle balancewith a simple neutral transport model[2,6].
We compare this C-S-D model with B2-EIRENE analysis results for the attached divertor of JT-60U[9],
and

the

following

goodagreement

isobtained;

Tsol = 51.4 eV(TsolB 2 ≈ 50 eV), Tdiv = 10.1 eV(TdivB 2 ≈ 12.0 eV),

B2
B2
nsol = 0.9 ×1019 m-3(nsol≈ 1.0×1019 m-3), ndiv = 2.3×1019 m-3(nsol≈ 3.0×1019 m-3) , where those inside brackets are B2-EIRENEresults. With this C-S-D model, we also reproduce the transition phenomenon from Low to High recycling state
as reported in ref.[7,8]. We apply this C-S-D model to the HT-7U(EAST) operational space. In the first phase ofHT-7U, the plasma current will be driven with LH current driving method, where low density is preferable. Incontrast, High recycling state of divertor is required to decrease heat load on the divertor plate. We carry out thepreliminary analysis for the operation space for both core and divertor plasma. We also apply this model to ITER
LH transition phase and find the possibility of the divertor density oscillation during the LH transition, which
may makes it difficult to control divertor plasma[2]. The modelling of the detached plasma condition remains tobe done. This work is partly supported by JSPS-CAS Core-University Program on Plasma and Nuclear Fusion.
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with a Tokamak Reactor under Foreseeable Physical and Engineering conditions”, Nucl. Fusion in press.
[2] R. Hiwatari et al., in Proc. Of the 9th International Workshop on Plasma Edge Theory in Fusion Devices, SanDieo, USA, 2003.
[3] N. Uckan and ITER Physics Group 1990 ITER Physics Design Guidelines:1989.
[4] T. Yamamoto, et al., Fusion Eng. Des. 39-40 (1998) 143.
[5] K. Borrass, Nucl. Fusion 31(1991)1035.
[6] N. Hayashi, et al., J. Nucl. Mater. 313-316(2003)1041.
[7] M.Sugihara, et al., J. Nucl. Mater. 128-129(1984)114[8] T.Takizuka,et al., JAERI-RESEARCH2003-010, 2003
[9] A.Hatayama, et al., Nucl. Fusion 40(2000)2009, J.Nucl. Mater. 290-293(2001)407