Modified Design of Aries T-Tube Divertor Concept

1. Modified Design of Aries T-Tube Divertor Concept Jeremy Burke ARIES-Pathways Project Meeting May 19, 2010

2. Original AREIES-AT T-Tube Design • 5 mm thick W armor • W alloy outer tube and inner cartridge • 15 mm diameter 100 mm long • Divertor would use ~110,000 units • He at 600 °C and 10 MPa • Transition zone going from W alloy tube to the steel channel • It is expected that the T-Tube divertor concept will be able to handle a 10MW/m2 heat flux.

3. Original T-Tube Thermo-Fluid Results • Thermal loads are calculated with a 10 MW/m2 heat flux on the plasma surface of the W armor, and a volumetric heat generation of 17.5 MW/m3 • Max jet velocity = 230 m/s • Coolant pressure drop = ~0.12 MPa • PPumping/Pthermal = ~5.7% (would like to keep this under 10%) • Max coolant temp = 1180 °C

4. Original Design Armor Temperature Distribution ΔT on plasma face = 225 °C

5. Original T-Tube Thermo-Mechanical Results • Temperature dependent material properties were attained from the ITER Material Properties Handbook • Max armor temperature = 1809 °C • Max tube temperature = 1268 °C (re-crystallization limit ~1300 °C ) • Max thermal and primary stresses = 342 MPa (3Sm limit = 450 MPa)

6. Original T-Tube Concept for ARIES-AT VS New Tapered Design • Subject to the same thermal loads and mass flow rate • Original cartridge - 10 mm diameter • New cartridge tapers from 10 mm to 2.5 mm at the ends • Armor Surface Heat Flux - 10 MW/m3 • Volumetric Heat Generation - 17.5 MW/m3 • He Mass Flow Rate - 8.45 g/s

7. New Thermo-Fluid Results • Thermal loads are calculated with a 10 MW/m2 heat flux on the plasma surface of the W armor, and a volumetric heat generation of 17.5 MW/m3 • Max jet velocity = 220 m/s • Coolant pressure drop = ~0.105 MPa • PPumping/Pthermal = ~5.7% (would like to keep this under 10%) • Max coolant temperature = 1161 °C

8. New Design Armor Temperature Distribution • ΔT on plasma face = 200 °C

9. New Thermo-Mechanical Results • The same ANSYS Structural setup was used • Max armor temperature = 1791 °C • Max tube temperature = 1246 °C (re-crystallization limit ~1300 °C ) • Max thermal and primary stresses = 368 MPa (3Sm limit = 450 MPa)

10. Results Comparison Tapered Design • Max Velocity – 220 m/s • Pressure Drop – 0.102 MPa • Max Coolant Temp – 1161 °C • Max Armor Temp – 1791 °C • Max Tube Temp – 1246 °C • Max Stress - 368 MPa • Plasma face ΔT = 200 °C • Original Design • Max Velocity – 230 m/s • Pressure Drop – 0.125 MPa • Max Coolant Temp – 1180°C • Max Armor Temp – 1809 °C • Max Tube Temp – 1263 °C • Max Stress – 342 MPa • Plasma face ΔT = 225 °C

11. Velocity Profile and Temperature Comparison • New T-Tube has slightly lower max temperature with a more even distribution. • New T-Tube has lower max velocity but the velocity at the end is higher, thus the more even temperature distribution

12. Future Work • To date only steady state thermal analysis has been done • Decision must be made on future analysis • Transient thermal loading can be analyzed • Plastic deformation analysis can be performed to determine if the design can be pushed passed the 3Sm limit and potentially go beyond a 10 MW/m2

13. W to Steel Joint Analysis • Graded transition from W alloy to steel manifold • Analysis still needs to be performed