Correlation between electrical properties and fluid flow in paper insulation

Both electrical conduction in oil-impregnated paper and fluid flow through the paper are impeded by the fact that the pores are tortuous. By an analogous reasoning to what has been done for water-impregnated porous rock, we claim that there is a relation between these two phenomena. The predictions of our theory are shown to be reasonable. We further argue that a high value of the tortuosity is beneficial for the behaviour of the insulation system.