PL FUSION Forschungszentrum Karlsruhe in der HelmholtzGemeinschaft FZK

PL FUSION Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft FZK - EURATOM ASSOCIATION He-cooled Divertor Development in the EU: The Helium Jet cooled Divertor HEMJ Presented by Thomas Ihli * Contributors: Divertor Group at FZK, Germany and Efremov Institute, Russia ARIES Meeting General Atomics, San Diego February 24 -25, 2005 * Forschungszentrum Karlsruhe, currently exchange visitor to UCSD & The ARIES Team 02/24/2005 T. Ihli 1

PL FUSION Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft FZK - EURATOM ASSOCIATION Introduction: Divertor Requirements Target plate X-point target length [m] Divertor with Target Plates heat flux [MW/m²] DEMO Divertor main requirements: • Heat load up to at least 10 MW/m² & strike point movements • Withstand erosive particle flux for several years (low sputtering rate) • He-cooling, high He-pressure ≈ 100 bars & vacuum leak tightness 02/24/2005 T. Ihli 2

PL FUSION Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft FZK - EURATOM ASSOCIATION EU Tungsten Divertor: General Design W Armor FZK 02/24/2005 W Alloy Cap ? He cooling Structure heat transfer enhancement + + - Ferritic steel (ODS) or W Alloy / Densimet W-Armor: High Melting Point High Heat Conductivity low Sputtering Rate activation accaptable need of low Impurity of W in Plasma (due to high atomic number of W) T. Ihli 3

PL FUSION Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft FZK - EURATOM ASSOCIATION Evolution of FZK Heat Transfer Design HEM P HEM S W 1300°C pin array HEM J 1300°C slot array jet array back-up reference simple fabrication max. heat flux 02/24/2005 T. Ihli 4

PL FUSION Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft FZK - EURATOM ASSOCIATION COOLING TECHNOLOGY: Jet Impingement Cooling technology Jet Impingement applied in the fields of: • Aircraft Engines HOT • Gas Turbines • Burners … DEMO Divertor 02/24/2005 T. Ihli 5

PL FUSION Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft FZK - EURATOM ASSOCIATION HEMJ Cooling Finger: Design & Materials W He (TS) Armor Tile Cap (W Alloy) Cartridge (Steel) (ELMs, disrupt. ) Disr. ) He 600°C (RCT) He Cap Thimble 700°C FZK 02/24/2005 1300°C Temp. Transition Piece STEEL 2500°C ~700°C (DBTT) ~ 600°C (DBTT) T. Ihli He 700°C 600°C Ferritic Steel (ODS) Armor (W) W alloy (e. g. WL 10) 3410 °C ~700 °C Bulk 300°C (DBTT) 6

Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft PL FUSION FZK - EURATOM ASSOCIATION High reliability, low waste during fabrication Construction Kit Principle: 9 -Finger Unit Test, Assembly 02/24/2005 Small Units advantageous for R&D progress Small Units can be tested before assembling Stripe-Unit Target Plate Test, Assembly Divertor Cassette Test, Assembly T. Ihli … 7

Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft PL FUSION FZK - EURATOM ASSOCIATION Details of 9 -Finger module Steel-plates and cooling fingers 9 -finger-module FZK W-section, 600 to 2000°C Collector section He, Steel: 600 to 700°C He He FZK Manifold section He, Steel: 600 to 700°C (Welding: Laser, E-Beam, diffusion welding or HIP) 02/24/2005 T. Ihli 8

PL FUSION Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft FZK - EURATOM ASSOCIATION Second joint 4 mm 1 mm First joint 20 mm Upper W layer with castellation (10 x 10 mm) 15 MW/m 2 700 cycles OK defect after add. 50 cycles at 16 MW/m 2 02/24/2005 T. Ihli EFREMOV under FZK contract R&D on fabrication technologies: high temperature W-joint 9

PL FUSION Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft FZK - EURATOM ASSOCIATION Brazing successful, EFREMOV under FZK contract R&D on fabrication technologies: high temperature curved W-joint survived up to 100 temperature cycles at 14 MW/m 2 02/24/2005 T. Ihli 10

PL FUSION Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft FZK - EURATOM ASSOCIATION W-Cap – Steel Joint (Efremov Inst. ) W-Cap – Steel-Tube Joint MOCKUP Cross-section of lock-area Cap W Cast copper layer Pins W Leak detected after 2 nd thermal cycle Transition piece steel 02/24/2005 T. Ihli 11

PL FUSION Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft FZK - EURATOM ASSOCIATION R&D on fabrication technologies: W-steel joint Finger mockup (without armour tile) after casting (left) and after posttesting examination (right). 100 thermocycles (pin=10 MPa) ok Main elements for W-Steel joint with new (conic) lock EFREMOV under FZK contract 02/24/2005 T. Ihli 12

PL FUSION Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft FZK - EURATOM ASSOCIATION Layout example for Multiple-He-Jet-Cooled Divertor Finger Unit W Multiple Jet Cartridge center hole; D = 1 mm a = 18 mm FZK W Alloy D = 15 mm 02/24/2005 jet-to-wall spacing H = 1. 2 mm Steel FZK 24 holes; D = 0. 6 mm T. Ihli 13

PL FUSION Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft FZK - EURATOM ASSOCIATION CFD-Results for layout example Flow Velocities Temperatures Temp. [°C] Tmax 1675 °C Mamax = 0. 13 a = 1770 m/s Veloc. [m/s] Tmax 1152 °C 230 0 IRS B. C. : Results: IMF III Helium, 10 MPa, T_in 630 °C, heat load: 10 MW/m²: • max. Temperature in W-Cap: 1152°C (< 1300°C) • Pressure drop: 0. 14 MPa • Mass flow per finger: 6. 8 g/s 02/24/2005 T. Ihli 14

PL FUSION Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft FZK - EURATOM ASSOCIATION Minimal He mass flow for different jet hole diameters HEM J heat flux: 10 MW/m² Recrystallisation J 1 a: D = 0. 6 mm J 1 d: D = 0. 7 mm J 1 e: D = 0. 85 mm 02/24/2005 T. Ihli 15

PL FUSION Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft FZK - EURATOM ASSOCIATION Armor – Cap Joint Improved Finger Design Stress intensity for bonded armor, 10 MW/m², 10 MPa Stress intensities depending on cap interface treatment and heat flux: ANSYS FE Connection “Bonded” “No separation” Stress Intensity 377 MPa 228 MPa 3 Sm at 1100°C ~ 460 MPa at 850°C ~ 580 MPa 02/24/2005 T. Ihli 16

Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft PL FUSION FZK - EURATOM ASSOCIATION Efremov GPF 2: Scheme & Mock-ups Caps (brass) Helium Heat Exchanger Water Pressure Vessels Mock up Pressure Tank Cartridges (steel) Compressor Heat Exchanger 02/24/2005 T. Ihli 17

PL FUSION Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft FZK - EURATOM ASSOCIATION GPF 2 RESULTS (Δp) for 2004 brass mock-ups 1000 HEMS Pressure drop [k. Pa] 24 x 0. 3 mm Reasonable layout: G = 7 g/s, dp = 100 k. Pa 100 HEMJ D = 0. 85 D = 0. 6 10 1 02/24/2005 Mass flow [g/s] 10 100 T. Ihli 18

PL FUSION Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft FZK - EURATOM ASSOCIATION GPF 2 RESULTS for 2004 brass mock-ups 20 CFD Calculation 18 GPF tests (Cu. Cr. Zr) Heat flux [MW/m 2] 16 14 12 10 8 HEMJ HEMS D = 0. 85 D = 0. 6 24 x 0. 3 mm 6 4 2 Mass flow [g/s] 0 02/24/2005 T. Ihli 19

Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft PL FUSION FZK - EURATOM ASSOCIATION HEMJ Layout for OB target (PPCS Model B) Zone 1 & 2 24 fingers zone length in parallel 432 mm Zone 3 38 fingers zone length in parallel 684 mm OB Zone 4 78 fingers zone length in parallel 1404 mm 3 4 2 HEXAGONAL TILE mass flow: 7. 9 g/s dp: 103 k. Pa (76%) heat flux: 11. 61 MW/m² holes: 24 x 0. 71 mm, 1 x 1. 47 mm 02/24/2005 SQUARE TILE mass flow: 5. 4 g/s dp: 55 k. Pa (69%) heat flux: 7 MW/m² holes: 24 x 0. 7 mm, 1 x 1. 47 mm SQUARE TILE mass flow: 2. 46 g/s dp: 37 k. Pa (60%) heat flux: 3. 2 MW/m² holes: 12 x 0. 7 mm, 1 x 1. 47 mm 1 T. Ihli OB 20

PL FUSION Forschungszentrum Karlsruhe in der Helmholtz-Gemeinschaft FZK - EURATOM ASSOCIATION Objectives: He-cooled Divertor on the way to ITER & DEMO Reactors Cassette, TDM DEMO ITER 2020 Targets Big Parts Development Materials, Design, Joining 9 -Finger-Units Finger Units Stripe-Units Small Parts Development 02/24/2005 T. Ihli 21