Magnetic topology effects on ion flows

We consider the effect of magnetic topology on the Pfirsch-Schl\"uter flows inside the separatrix of a tokamak for reversal in the direction of (i) the plasma current or poloidal magnetic field, (ii) the toroidal magnetic field, or (iii) both; and for (iv) a switch between lower and upper X-point operation. We find that the results of the magnetic topology changes on the flows observed in Alcator C-Mod are consistent with the predictions of neoclassical theory when both the up-down symmetric and up-down asymmetric drives for toroidal rotation are retained.