Twisted Racetrack Revisited Model Changes: Side A has 10 turns Clamps have been modified to as built geometry. Property Changes (linear results only as of ): E Shell = 22 E6 psi [Eshell = 23 E6 psi (nonlinear)] E Winding = 8.5 E6 psi [Eshell = 9 E6 psi (nonlinear)] Model includes: Clamp Preload = 125 lbs. Thermal shrinkage of 0.04% (400με) to account only for the cool- down to cryogenic. Magnetic nodal force loading for ¾ of the max current (42 kAmps) used for the real coils.

Geometric changes to clamps Clamps are now accurately represented by exact dimensions to machined parts. New ( ) Old ( )

Updated Mesh Properties Change: E Shell = 22 E6 psi E Winding = 8.5 E6 psi

Electric Potential / Magnetic Forces Electric potential (volts) Magnetic forces (N/node) A B Side A = 10 turns Side B = 9 turns Loading from 1kAmp operating current (to be scaled in global model)

Magnetic Field Intensity for 1000 A (Tesla) A B Side A, 10 turns Side B, 9 turns

Total Deflection (Linear run) Current = 31.5 kAmps Side A, 10 turns Side B, 9 turns Constraint (fixed B/C)

Stress Intensity (linear) Current = 31.5 kAmps Side A, 10 turns Side B, 9 turns

Stress Intensity (linear) Modular Coils Only Current = 31.5 kAmps Side A, 10 turns Side B, 9 turns

Max Principal Strain (linear model) 42 Kamps/turn Current = 31.5 kAmps Side A, 10 turns

Non-linear Winding is allowed to slide along tee: Contact behavior is set to “frictionless”

Deflection (nonlinear) Current = 31.5 kAmps Side A, 10 turns Side B, 9 turns Constraint (fixed B/C) Non-linear =.37 in Linear =.20 in

Stress Intensity (nonlinear) Current = 31.5 kAmps Side A, 10 turns Side B, 9 turns Non-linear = 47 ksi Linear = 28 ksi

Stress Intensity (nonlinear) windings only Current = 31.5 kAmps Non-linear = 10 ksi Linear = 12 ksi

Stress Intensity (nonlinear and linear) windings only Current = 31.5 kAmps 10 ksi Non-linear Side A, 10 turns, Linear Side A, 10 turns, 12 ksi

Max Principal Strain Current = 31.5 kAmps Current = 42 kAmps

Max Gap is.00519” or mm. Contact Element Gap Plot Red = winding/tee touching Gap Scaled by 25 X Current = 31.5 kAmps

Contact Element Gap Plot Current = 31.5 kAmps Side A, 10 turns Side B, 9 turns

Clamp Stresses Max clamp stress = 14.2 ksi 42 Kamps/turn

Measuring Strain on the actual racetrack Perhaps the easiest way to correlate strain measurements is to relate the modeled strain to the already defined coordinate systems The coordinate systems are oriented with the x- direction following the winding direction (see Figure) The coordinate systems are located at both the midpoint between clamps and the clamps themselves

Strain gage “V and Y”, on side A of Tee, near clamp 17 Side A, 10 turns Winding strain = 4.1 e-3 in/in Tee strain = 1.2 e-3 in/in X-Directional Strains

Strain gages “V and Y”, on side A of Tee, near clamp 17 Side A, 10 turns Winding strain = e-3 in/in Tee strain = -0.61e-3 in/in Z-Directional Strains

Strain gage “W and Z” on side B of Tee, near clamp 39 Winding strain = 1.4 e-3 in/in Tee strain = 2.0 e-3 in/in Side B, 9 turns X-Directional Strains

Strain gage “W and Z” on side B of Tee, near clamp 39 Winding strain = e-3 in/in Tee strain = e-3 in/in Side B, 9 turns Z-Directional Strains

Strain gage “X” on clamp 39 X directional Strain Y directional Strain X strain = e-4 in/in Y strain = e-3 in/in

Comparison of TRC analysis to Global NCSX Modular Coil analyses Ranges for expected max stress/strain on the tee and windings Modular coil analysis 11/1/04

Summary Table OLD VALUES *Note: nonlinear runs have E shell = 23E6 psi and E winding = 9E6 psi

Temperatures during the 10 th shot Temperature after the 10 th shot Temperature after the 10 th cool down 15 minute cool down

After 10 th cycle (winding and tee isolated) 15 minute cool down