EuCARD2 MagnetStatus and action plan

19/09/2014

Maria DURANTEThanks to EuCARD2 Task 10.3 members

Magnet concepts under studyStarting from cable propositions from Task 10.2 :• Block / stacked tapes cable

• Aligned Block design

• Cosine-theta design• CCT design

2

Block with YBCO stacked tapes cable

• Low cost cable• Woundable cable : “twist and bend” to avoid hardway bendingBUT • Non-continuous transposition of the stacked tapes cable transposition at coil ends or between coil layers

• Mechanical strength, twisted regions

3

John Himbele

JE = 400 A/mm²

Block with YBCO stacked tapes cable - status• 2D Electromagnetic design done• 3D electromagnetic design on going• Twist region configuration studies on going• FE Magnet mechanical model to be done• Winding test set up under study • tapes block transposition• twist region mechanical support

4

Aligned block with YBCO Roebel cable

5

Mag

netic

Fie

ld [T

]Pe

rcen

tage

on

Load

line

[%]

The two plots present flux path variation for insert magnet: (left) standalone in Iron ,(right) in 13T ideal background field

Note! Yellow area is the high short sample position.

Very different from std. LTS magnets.

Jeroen Van Nugteren

Aligned block with YBCO Roebel cable - status• 2D and 3D Electromagnetic design done• End optimization done• Mechanical model of the Roebel cable done• Tests on Roebel cable insulation and mechanical reinforcement on going• FE Magnet mechanical model to be done• Sub scale model FeaTher-M0 • Aim: Quench detection & coil production• Electromagnetic Design completed• Components almost ready End of September• At least 3 short scale models are foreseen : First SS one by the end of the year

SC Roebel cable needed for the others• HTS insert magnet proposal (EuCARD2 baseline?) : Feather-M2• CAD design ongoing

6

Cosine-Theta with YBCO or BSCCO cable

YBCO Roebel cable

3.7 T

BSCCO Rutherford cable

3.7 T

Table X1: Lorentz forces in [kN/m] on coil blocks of the HTS insert in both configurations and for a hypothetical** Je = 600 A/mm² HTS magnet inserted in: the iron yoke Fresca2 Fresca2 (Je = 600 A/mm²)**

Block1* (Fx Fy) = Block2 (Fx Fy) = Block3 (Fx Fy) = Block4 (Fx Fy) = Block5 (Fx Fy) = Block6 (Fx Fy) = Block7 (Fx Fy) =

(74, -8) (80, -9) (45, -7) (50, -5)

(20, -23) (86, -74) (85, -36)

(328, -8) (333, -9) (172, -9) (176, -5)

(401, -23) (721, -78) (401, -38)

(458, -13) (467, -16) (244, -15) (250, -9)

(525, -40) (969, -137) (557, -67)

Fxtotal = 2x49 tons/m Fxtotal = 2x258 tons/m Fxtotal = 2x354 tons/m *Block number (see Fig. X1) **R&D target value [cf. intermediate report on Task 10.2] leading to a central field of 18 T instead of 16.75 T

HTS dipole inside FRESCA2 magnet - Lorentz forces

7

Clément Lorin

Iron yoke

5 T

• First cos-theta design proposal: 2 layers, 10-mm wide Roebel cable• 2D Electromagnetic design done• End optimization ongoing• FE Mechanical model done

Slidingcontacts

Initial displacement to simulate the prestress due to the press + welding

Collar extremity free displacement

X

Y

Symmetry :-vertical: collar + external tube-horizontal: coil only

Contact :-glued: coil + wedges + insulation (coil block)-sliding: collar with external tube or coil block

Field [T] ET thickness [mm]

Prestress Peak stress [MPa]

5.00 5.5 Yes 1465.00 5.5 No 1185.00 8.0 Yes 1875.00 8.0 No 100

16.78 5.5 Yes 78216.78 5.5 No 68416.78 8.0 Yes 80516.78 8.0 No 600

5.00 20.0 No 3016.78 20.0 No 250

Cosine-Theta with YBCO Roebel cable - status

Show stopper: Mechanical structure for double layer cosine-theta too weak.

• First cos-theta design proposal: 2 layers, 10-mm wide Roebel cable• 2D Electromagnetic design done• End optimization ongoing• FE Mechanical model done show stopper

• New design proposals under study• Cos-theta 1 layer / thicker structure design• 12 mm Roebel cable• Mechanical design done

• Short model coil to be designed• CAD detailed design foreseen from Nov 2014

Cosine-Theta with YBCO Roebel cable - status

12 mm 15.5 mm

Field [T]

ET thickness [mm]

Prestress Peak stress [MPa]

5.00 15.5 Yes 2205.00 15.5 No 35

17.16 15.5 Yes 57017.16 15.5 No 150

Seems to be achievable.

Activities at CEA next year

Spares

11

Task 10.3 SCHEDULE

12

Task 10.3 DELIVERABLE AND MILESTONESEuCARD² Deliverable and milestones• D10.1 Conceptual study of HTS accelerator magnets (report) M18

The report must contain all key elements of the novel magnet design, considering electromagnetics, mechanical, thermal, stability and protection aspects.

• MS64 YBCO magnet design report M18• MS68 Technical and economical comparison YBCO/Bi2212 magnets M36

Internal milestones proposal• IMS01 Inputs for magnet HTS design M3• IMS02 HTS magnet(s) detailed design M24• IMS03 HTS magnet(s) built M40

D10.4 for task 10.4 : Magnet Cold test M44

13

Magnet specificationsParameter name Symbol Value

YBCO MagnetValue

Bi-2212 Magnet Remarks

MAGNET

Central field B0 5 T Up to 5 at 4.2 K (20% margin on loadline)

Clear bore aperture Φb 40 mm 40 High energy LHC dipole magnet (beam size 25-28 mm)

Operational temperature T 4.2 K 4.2 1.9 K also possible77 K tests during magnet realization

Current at 20 T I 5 to 10 kA 5 to 10

Stray magnetic field Bout ≤ 0.2 T At border of cryostat

Magnetic multipoles at 2/3 Φb bn 5 10-4 - Geometric

Magnetic multipoles at 2/3 Φb bn 30 10-4 - Including magnetization and persistent current (best effort)

Magnetization M 300 mT 300 Allowing fast ramping up

Straight section length L ≥200 mm ≥200 As short as possible while remaining compatible with field quality for YBCO

Magnet length LM < 1500 mm700 mm uniform field (Fresca2)Grenoble test facility

Magnet outer diameter ΦM< 99 mm ()

< 140 mm x 90 mm (rect) Without yoke – Outsert candidates : FRESCA2 (100 mm) or EDIPO (143 mm x 93 mm)

CONDUCTOR

Engineering critical current density (20T, 4.2K) JE, 20T 600 A/mm² In strand/tape at field perpendicular to wide

face

Available cable Engineering critical current density (20T, 4.2 K) JE, 20T 400 A/mm² For small development magnets

Bare cable width wcbl 10-12 mm 10-15 Provisional

Bare cable thickness at 50 MPa tcbl 0.8-1.2 mm 1.5-2.0 Provisional

14