Deformation and mechanical stresses in a magnet with thin-walled quasi-force-free winding

The factors leading to an increase in the mechanical stress in the winding of solenoids are considered on the example of a thin-walled magnet with a multi-turn quasi-force-free winding. This example is compared with an ideal system in the form of a solenoid with unlimited length and continuous current distribution. A method for measuring submicron-sized dynamic deformations of the winding in a pulsed field has been developed and verified by comparing experiment results and calculations. Numerical modelling allowed us to distinguish the influence of local edge effects determined by characteristics of the field distribution in the inter-turn gaps. Numerical calculations have shown how the mechanical properties of the material surrounding the coil affect the stress in the winding. The possibility of reducing the stress by increasing Young's modulus of the material was confirmed. The Influence on the strength of axial forces that arise near the edges of the turns and lead to compression of the turns in the axial direction is revealed.