Stress calculations for high magnetic field coils

Abstract

A computer program is described which enables calculations to be made of all components of the stress in uniform current density coils used for producing intense magnetic fields. Particular reference is made to wire-wound pulsed field coils, but the technique is appropriate to all types of solenoids including superconductors. The effect of the elastic properties of the insulation is taken into account and shown to be important.Three separate types of coil are considered: unreinforced coils; coils reinforced with external cylinders; and coils reinforced with both external and internal cylinders. Charts are presented which give the maximum stress differences ΔS=Sθ-Sz and hence the maximum field strength for different geometries and cylinder thicknesses.Experimental results are presented for tests on a particular pulsed field solenoid wound from copper wire. These results are shown to be in agreement with the predicted values.