Published online by Cambridge University Press: 12 April 2013
Simple wire models have been proposed to simulate magnetic configurations in tokamaks. Here we consider electric currents in five parallel infinite wires to obtain double-null magnetic surfaces with specific choices of magnetic axis positions, triangularity, and elongation. As an example, we choose the position and the electric current of each wire to obtain magnetic surfaces similar to those expected in the tokamak international thermonuclear experimental reactor. Moreover, we also integrate the perturbed field line differential equation to simulate chaotic layers near the hyperbolic points and deposition patterns at the divertor plate observed in tokamaks. To simulate that, we add to the model a perturbing error field, due to asymmetries in the tokamak coils, and introduce a random collisional term to the field line mapping to reproduce escape pattern alterations due to particle collisions.