Evaluating Impact of TF Coil Deformations Under EM Load on Magnetic Field Quality Coil Deformations provided by Len Myatt’s ANSYS Structural Analysis of New TF for 5 Cases: –Cooldown Only –Cooldown + 0.5T –Cooldown + 1.7T Ohmic –Cooldown + 2 T High  –Cooldown + Equilibrium ID 7 Data Sorted and Converted to Filament Coil Format to produce Error Field from EM Deformation –Cooldown Only deformation subtracted from Cooldown + EM deformations Coil Sets run thru VACISLD Code to assess resonant field errors and impact on Magnetic Island size Conclusion: No Significant Impact –Worse Case Islands ~ 1.2% Total Flux for EQ ID 7 –Other operating scenarios significantly less than 1%

No Significant Impact of TF Deformation Under EM Loading on Magnetic Islands in Plasma Worse Case “Eq ID7” not a true operating point, but would still be acceptable Note: Islands are measured with respect to the VMEC M50 Plasma Equilibrium TF Deformations from Len Myatt’s Oct 25, 2004 Analysis

Unsorted Ansys Element Centroid Data

Sorted Ansys Element Centroid Data