Numerical analysis of time-dependent field perturbations due to gaps and holes in the shell of a reverse field pinch device

The paper describes how a finite element technique has been applied to the dynamic analysis of magnetic field configurations produced by a passive conducting shell in a fusion device. The relevance of the problem in the design of Reverse Field Pinch (RFP) magnetic fusion experiments is firstly pointed out, then the numerical method developed for this kind of applications is described. The technique has been applied to the design of the poloidal field system of RFX, a large RFP device now under construction [1]. The most significant results of the analysis and a discussion on the field control possibilities are finally reported.