DTT: a Divertor Tokamak Test facility for the study of the power - PowerPoint PPT Presentation

DTT: a Divertor Tokamak Test facility for the study of the power exhaust issues in view of DEMO R. Albanese, ENEA-CREATE (Italy) on behalf of the WPDTT2 Team & the DTT report contributors (work carried out in tight cooperation with WPDTT1)

Outline • WPDTT2: objectives, organization, activities • Project status − DTT requirements − Choice of parameters − DTT proposal • Conclusions R. Albanese | 1st IAEA Technical Meeting on Divertor Concepts | 29 SEPT. – 2 OCT. 2015 | PAGE 2

WPDTT2: objectives, structure, schedule Objective: design an experiment addressed to the solution of the power exhaust issues in view of DEMO. This derives from the need to develop integrated, controllable exhaust solutions for DEMO including plasma, PFCs, control diagnostics and actuators, using experiments, theory and modelling, so as to mitigate the risk that conventional divertor might not be suitable for DEMO . http://users.jet.efda.org/iterphysicswiki See also I-11: H. Reimerdes www.create.unina.it/dtt2 http://fsn-fusphy.frascati.enea.it/DTT 8 RUs: About 60 MEUR not yet allocated (mostly for HW) R. Albanese | 1st IAEA Technical Meeting on Divertor Concepts | 29 SEPT. – 2 OCT. 2015 | PAGE 3

WPDTT2: objectives, structure, schedule Steps of WPDTT2 Project Phase I Phase II FIRST TWO STEPS FURTHER STEPS MAINLY IN SUPPORT MORE FOCUSED TO PHYSICS ACTIVITIES ON DESIGN ACTIVITY OF WPDTT1 WITH THE SUPPORT OF WPDTT1 START OF STEP 4 ANTICIPATED TO APRIL 2015 TIGHT COOPERATION, SAME PB, COORDINATED TIME PLAN, SMOOTH HANDOVER WPDTT1/WPDTT2 R. Albanese | 1st IAEA Technical Meeting on Divertor Concepts | 29 SEPT. – 2 OCT. 2015 | PAGE 4

WPDTT2: objectives, structure, schedule welcomed by the General Assembly Opportunity (EFSI: Juncker’s plan) in March 2015 R. Albanese | 1st IAEA Technical Meeting on Divertor Concepts | 29 SEPT. – 2 OCT. 2015 | PAGE 5

WPDTT2: objectives, structure, schedule ANTICIPATION R. Albanese | 1st IAEA Technical Meeting on Divertor Concepts | 29 SEPT. – 2 OCT. 2015 | PAGE 6

Project status : DTT requirements e ,  * =L d / λ ei , • Preservation of 4 dimensional or dimensionless parameters: T Δ d /λ 0 , β + relaxation on normalized Larmor radius ( ρ i / Δ d )*R 0.75 P sep /R  15 MW/m • • Flexibility in the divertor region so as to possibly test several divertors • Possibility to test alternative magnetic configurations • Possibility to test liquid metals • Integrated scenarios (solutions to be compatible with plasma performance and technological constraints of DEMO) • Budget constraint (within a reasonable cost) R. Albanese, F. Crisanti, B. P. Duval, G. Giruzzi, H. Reimerdes, D. van Houtte, R. Zagorski, “DTT - An experiment to study the power exhaust in view of DEMO”, Presented at the3rd IAEA DEMO Programme Workshop (DPW-3) , Hefei, China, 11-15 May 2015 R. Albanese | 1st IAEA Technical Meeting on Divertor Concepts | 29 SEPT. – 2 OCT. 2015 | PAGE 7

Project status : Choice of parameters MAIN DTT PARAMETERS FOR THE REFERENCE SINGLE NULL SCENARIO b N R (m) 2.15 1.5 t Res (sec) a (m) 0,7 8 I P (MA) 6 V Loop (V) 0.17 B T (T) 6 Z eff 1.7 V (m 3 ) 33.0 P Rad (MW) 13 P ADD (MW) 45 P Sep (MW) 32 H 98 1 T Ped (KeV) 3.1 <n e > (10 20 m -3 ) n Ped (10 20 m -3 ) 1.7 1.4 b p n e /n eG 0.45 0.5 P Div (MW/m 2 ) (No Rad) <T e > (KeV) 6.2 ~ 55 t (sec) 0.47 P Sep /R (MW/m) 15 n e (0) (10 20 m -3 ) 2.2 P Tot B/R (MW T/m) 125 λ q (mm) T e (0) (KeV) 10.2 ~ 2.0 R. Albanese | 1st IAEA Technical Meeting on Divertor Concepts | 29 SEPT. – 2 OCT. 2015 | PAGE 8

Project status : Comparison with other devices Table compiled with the info available to us just to provide a comparison at a glance: some figures might be different for other devices in high performance scenarios R. Albanese | 1st IAEA Technical Meeting on Divertor Concepts | 29 SEPT. – 2 OCT. 2015 | PAGE 9

Project status : DTT Program R. Albanese | 1st IAEA Technical Meeting on Divertor Concepts | 29 SEPT. – 2 OCT. 2015 | PAGE 10

Project status: DTT proposal TD03-I: WP DTT2 Progress Report on the Italian EFSI proposal for DTT submitted to preconceptual “ baseline “design of DTT the Italian Government (July 2015) EFDA_D_ 2D3KX2 (Apr. 2015) R. Albanese et al., “Status and Perspective of the Project of a Exhaust Systems “, XXII AIV, Genova, Italy, 20-22 May 2015 Nuclear Fusion Infrastructure for Testing Alternative Power https://idm.euro-fusion.org/?uid=2D3KX2 http://fsn-fusphy.frascati.enea.it/DTT R. Albanese | 1st IAEA Technical Meeting on Divertor Concepts | 29 SEPT. – 2 OCT. 2015 | PAGE 11

Project status: DTT proposal R. Albanese | 1st IAEA Technical Meeting on Divertor Concepts | 29 SEPT. – 2 OCT. 2015 | PAGE 12

Project status: DTT proposal Plasma scenarios 6 MA SN scenario Plasma-wall gaps  40 mm (power decay length at 6 MA is  2 mm at the outboard midplane); • • plasma shape parameters similar to the present design of DEMO: R/a≈3.1, k≈1.76, <δ>≈0.35; • pulse length of more than 100 s (total available flux ≈ 45 Vs, Central Solenoid swing ≈ 35 Vs). R. Albanese | 1st IAEA Technical Meeting on Divertor Concepts | 29 SEPT. – 2 OCT. 2015 | PAGE 13

Project status: DTT proposal Conventional and alternative magnetic configurations that can be obtained using the DTT PF system. CS, PF and TF coils are superconducting: plasma pulse duration ~ 100 s without current drive R. Albanese | 1st IAEA Technical Meeting on Divertor Concepts | 29 SEPT. – 2 OCT. 2015 | PAGE 14

Project status: DTT proposal Internal copper coils can be used for plasma control or local modifications of the magnetic configuration in the divertor region See also P-2: F. Crisanti R. Albanese | 1st IAEA Technical Meeting on Divertor Concepts | 29 SEPT. – 2 OCT. 2015 | PAGE 15

Project status: DTT proposal Magnet system: CS, PF coils and TF Coils 18 TF coils: B peak : 12.0 T, B plasma : 6.0 T, 65 MAt; 6 CS coils: B peak : 12.5 T,  k |N k I k | =51 MAt; available poloidal flux:  17.6 Vs; 6 PF coils: B peak : 4.0 T,  k |N k I k | =21 MAt. in-vessel coils CS, PF coils and TF Coils DTT R. Albanese | 1st IAEA Technical Meeting on Divertor Concepts | 29 SEPT. – 2 OCT. 2015 | PAGE 16

Project status: DTT proposal Each of the 18 D-shaped TF coils has78 turns of Nb 3 Sn/Cu CIC conductor, carrying 46.3kA He cooled (inlet T of 4.5K): max field 11.4 T, max ripple on the plasma  0.8% Graded solution: Cable-In-Conduit (CIC) conductor layouts: 48 LF turns with thicker 316 LN jacket and lower SC strand number, 30 HF turns. section wound in pancakes to reduce the He path NI=65 MAt, Wm=1.96 GJ,  T marg = 1.2 K von Mises stress  OK (<650 Mpa in 3D analyses) Thotspot also OK (104 K all materials, 268 K Cu & SC only) Based on ITER-like strands with slightly optimized performances, only 20% higher, which should be achievable Jmax ~1.8 higher than ITER: possible SULTAN or EDIPO test facility for both HF & LF grade and the test of full-size joints If needed, a small reduction of Bmax by 5% would increase current density limit by 20% in the HF grade and 10% in the LF grade R. Albanese | 1st IAEA Technical Meeting on Divertor Concepts | 29 SEPT. – 2 OCT. 2015 | PAGE 17

Project status: DTT proposal The CS operates at 12.5 T (13.2 T peak on the SC) and consists of 6 independent modules based on Nb 3 Sn CICCs: 23 kA, 2220 turns (2x270+4x420). NI=51 MAt, Flux swing of 35 Vs,  T marg = 1.5 K von Mises stress OK for a 2.9 mm 316 LN jacket*: 346 Mpa T hotspot also OK (86K all materials, 229K cable only) ITER vs DTT CS ITER CS DTT CS Operating current (kA) 45.0 23.0 Peak magnetic field (T) 13 13.2 Cumulative operating load 585 kN/m 288 kN/m Conductor outer dimensions 49.0 mm x 49.0 mm 31.6 mm x 19.8 mm 8.2 mm Jacket Thickness 2.9 mm (minimum value) 771 Cable area (mm2) 353 (excluding central channel) DTT CS coil assembly Steel section per turn (jacket) 1566 mm2 242.4 mm2 *900 MPa yield stress R. Albanese | 1st IAEA Technical Meeting on Divertor Concepts | 29 SEPT. – 2 OCT. 2015 | PAGE 18

Project status: DTT proposal The 6 NbTi PF coils are in not-challenging conditions: separately fed, double-pancakes, placed into clamps fixed to the TF coil structure,3mm thick epoxy-resin layer for ground insulation around windings. Current and voltage limits (4 quadrants) Name Isat Vsat (V) turns Vertical force limits (12.5 MN for CS coils, (kA) 19 MN for PF coils) scaled from DEMO. CS3U 23 800 270 CS2U 23 800 420 Field and current limits CS1U 23 800 420 PF1 PF2 PF3 PF4 PF5 PF6 CS1L 23 800 420 Bmax (T) 3.70 3.00 2.35 3.36 3.85 4.02 CS2L 23 800 420 CS3L 23 800 270 Imax (MAt) 3.277 2.446 2.371 3.454 3.337 6.046 PF1 25.2 800 130 PF2 22.6 800 108 PF3 21.2 1000 112 PF4 24.7 1000 140 PF5 23 800 152 PF6 23.3 800 260 C1 60 50 1 C2 60 50 1 C3 60 50 1 C4 60 50 1 C5 25 200 4 C6 25 200 4 C7 60 50 1 C8 60 50 1 R. Albanese | 1st IAEA Technical Meeting on Divertor Concepts | 29 SEPT. – 2 OCT. 2015 | PAGE 19