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ITER In-Vessel Coils (IVC) Interim Design Review Thermal Structural FEA of Feeders. A Brooks July 27, 2010. Middle and Lower ELM Feeders Analysis Status Overview. Geometry Modeling & Meshing Feeders Background Field Coils Material Properties Boundary Conditions Temperature
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ITER In-Vessel Coils (IVC)Interim Design ReviewThermal Structural FEA of Feeders A Brooks July 27, 2010 ITER_D_353BL2
Middle and Lower ELM FeedersAnalysis Status Overview • Geometry • Modeling & Meshing • Feeders • Background Field Coils • Material Properties • Boundary Conditions • Temperature • Implied Structural Supports • Loading • Ohmic Heating • Nuclear Heating • Lorentz Forces • Water Pressure • Preliminary Results • Stress Allowables and Acceptance Criteria (TBD) • Ongoing Analyses • Issues and Resolution Plan ITER IVC IDR 26-28 July 2010
Feeder Geometry Modeling Interface is up to but not including Couplings ITER IVC IDR 26-28 July 2010 CATIA Model Exported as Step File and Imported into ProE
Modeling • Modeling used section data and sweeping curves from CAD Model to create mesh using FORTRAN Codes ITER IVC IDR 26-28 July 2010
PF and TF Field Drivers • PF Coils Modeled Explicitly in ANSYS • TF Coil uses 1/R from Center Filament to Provide 5.3T at 6.2m Initial Scenario Data Used Other Scenarios need to be considered ITER IVC IDR 26-28 July 2010
Material Properties • Preliminary Analysis – Using Linear Properties ITER IVC IDR 26-28 July 2010
Boundary Conditions • Preminary Analyses Assumed MgO bonded to Cu Tube and SS Sheath • Impact of debonding to be addressed using low shear modulus • Supports not modeled explicidly, constraints added at support locations • Initial runs assumed tee fully bonded to VV structurally but isolated thermally (conservative?) • Tube Ends Fully Constrained at Couplings (assumes support will exist) • Only Cooling from Water Tubes • ID held at fixed temperature: 100C at inlet, 130 at outlet • Radiation from outer surfaces to VV and surroundings not included • Conduction cooling to VV ignored ITER IVC IDR 26-28 July 2010
Loading • Ohmic Heating 15 kA DC Current in Cu • Directions chosen to induce worse moments of Tee Section – Top Turns in one direction, bottom opposite • Note: Since Temperature is constrained at ID (perfect cooling) Ohmic heating has only small effect on Cu transverse temperature gradients. • Nuclear Heating assumes 1.4 MW/m2 at Plasma facing surface and decays as e-x/l where l= 6 cm • Lorentz Forces from 15kA crossed with local field from OH/PF and TF (see plots) • 4.4 MPa (638psi) Water Pressure in Tubes ITER IVC IDR 26-28 July 2010
Applied Nuclear Heating Heat Generation Rates ITER IVC IDR 26-28 July 2010
Resulting Steady State Temperatures Mid Section of Feeders ITER IVC IDR 26-28 July 2010
Resulting Steady State Temperaturesat ends of Feeder Tees With Cold Inlet Water in Bottom Turn, Hot Spot is on Top With Cold Inlet Water in Top Turn, Hot Spot is on Bottom ITER IVC IDR 26-28 July 2010
Water Pressure in Tubes ITER IVC IDR 26-28 July 2010
Toroidal Field 1/R Field plus self field from feeders ITER IVC IDR 26-28 July 2010
Vertical Field Initial Results ignored plasma field, but for outboard components vertical field is increased Without Plasma With Plasma ITER IVC IDR 26-28 July 2010
Radial Field As is radial field Without Plasma With Plasma ITER IVC IDR 26-28 July 2010
Global Von Mises Stresses ITER IVC IDR 26-28 July 2010
Global Displacements ITER IVC IDR 26-28 July 2010
EM vs Thermal Loads Impact onVon Mises Stress View from Back Thermal EM ITER IVC IDR 26-28 July 2010
EM vs Thermal Loads Impact onDisplacements Thermal EM ITER IVC IDR 26-28 July 2010
Von Mises Stress at Mid Section Temperature Gradient Between base and VV And assumption of fixed Support causes large stress ITER IVC IDR 26-28 July 2010
Von Mises Stress at Lower End Section Local stress concentration at weld ITER IVC IDR 26-28 July 2010
Von Mises Stress in Tubes at Mid ELM High Outer fiber stress From bending of Unsupported tube ITER IVC IDR 26-28 July 2010
Von Mises Stress at Mid Section with Perfect Thermal Contact to VV Stress in SS base drops significantly 278=>150 MPa ITER IVC IDR 26-28 July 2010
Von Mises Stress at Lower Section with Perfect Thermal Contact to VV Local stress concentration at weld still persists ITER IVC IDR 26-28 July 2010
Von Mises Stress at Lower Section with Perfect Thermal Contact to VV Only minor change in Outer fiber stress From bending of Unsupported tube ITER IVC IDR 26-28 July 2010
Stress Allowables and Acceptance Criteria • Need to ensure compliance with Appendix D of the In-Vessel Component Criteria specifies the Stress Acceptance Criteria. Not there yet for unsupported tubes and welds. MgO TBD ITER IVC IDR 26-28 July 2010
Ongoing Analyses • Alternate Support Concepts need to be evaluated to reduce stresses • For Tee • For Tubes • Additional Load Cases need to be identified and run • Normal Operating Scenarios • Disruption Scenarios • Transient Response • Characterization of MgO, which is in progress, needs to be folded into analyses • Material Properties • Interface behavior with Cu Tube and SS Casing ITER IVC IDR 26-28 July 2010
Issues and Resolution Plan ITER IVC IDR 26-28 July 2010