Effect of eddies on convected space charge density in relaxation tanks

The paper reports the effects of eddies on charge distribution in relaxation tanks of shapes which could be employed in petroleum or transformer industries using a `rotated finite difference scheme´. The notable features of the numerical scheme used are the incorporation of the coupling between the flow and the charge, and defining the charge on the wall as an unknown in calculating the charge distribution. The results show that eddies are formed in the cavity region at relatively low Reynolds numbers (inlet velocity=10 cm/s) and their structure depended on the inlet velocity and the enlargement angle. At low inlet velocities eddies occupied only a small portion of the cavity region; however, at high inlet velocities (⩾50 cm/s), the eddy almost occupied the entire cavity depth. The paper discusses the interaction of these eddies on the convected charge in the relaxation tanks for different flow conditions