@misc{oai:repo.qst.go.jp:00066798,
 author = {Asakura, Nobuyuki and Hoshino, Kazuo and Tokunaga, Shinsuke and Shimizu, Katsuhiro and Uto, Hiroyasu and Kudo, Hironobu and Tobita, Kenji and Noriyashu, Ohno and 朝倉 伸幸 and 星野 一生 and 徳永 晋介 and 清水 勝宏 and 宇藤 裕康 and 工藤 広信 and 飛田 健次},
 month = {May},
 note = {Power handling in the main plasma and divertor has been investigated in steady-state Japan Demo concept of 1.5 GW-level fusion power and the major radiaus of Rp = 8.5m. System code (TPC) survey for the Ar impurity seeding suggested the designed <ne> of 6.6-7.2x1019m-3 was lower than that in ITER. The divertor plasma simulation (SONIC) was performed in the divertor leg length of 1.6 m with the fixed exhaust power to the edge of Pout = 250MW and the total radiation fraction of frad = Prad/Pout = 0.8, as the first step to investigate appropriate design of the divertor size and geometry. Appropriate fuel and Ar puff rates were determined, where Praddiv was ~150MW (fraddiv ~ 0.6), (nAr/ne)SOL was decreased to 0.4-0.45% and nemid was increased to 2.3-2.4x1019m-3. In the outer divertor, the significant radiation peak was maintained in the divertor leg (near the separatrix) at 0.9-1.2 m below the X-point. At the outer target, partial detachment was produced near the strike-point (rdiv < 15 cm), and the peak qtarget at the attached region was ~5 MWm-2. At the inner divertor target, full detachment of ion flux was not produced due to Tediv = Tidiv ~1eV, and the peak qtarget was also ~5 MWm-2 mostly due to the surface-recombination. These results suggest a power exhaust scenario in Demo and the divertor design concept with long leg length, in which the peak-qtarget can be reduced less than 10 MWm-2 for both inner and outer divertor., 22nd International Conference on Plasma Surface Interactions in Controlled Fusion Devices},
 title = {Simulation Studies of the Divertor Geometry and Plasma Parameters for 1.5 GW Fusion Power Demo Reactor},
 year = {2016}
}