Stress analysis of PLT [Princeton Large Torus] coil

The toroidal field coils of tokamak devices create a field within the torus whose strength varies inversely with distance from the machine center. This field, crossing the current in the TF coils, creates a magnetic pressure on the coil. The pressure produces a net inward centering force, countered by pressure on the wedge face, and a vertical separating force, causing tensile stress across the horizontal mid-plane. In the past these forces have been analyzed by superposition and beam theory. Because of the size and complexity of the PLT machine it was decided to also initiate a finite element analysis of the coil. This paper describes both methods of analysis. 9 refs., 7 figs., 2 tabs