Stream function distribution of petroleum liquids in relaxation tanks

One important issue related to safety in handling petroleum liquids is the problem of charge relaxation of the low conductivity petroleum liquid in storage tanks. A relaxation tank placed in the upstream of the storage tank can considerably reduce the charging level of the liquid that enters the storage tank. In order to design a more effective relaxation tank, the stream function distribution of the liquid should be known accurately. In this paper a novel “rotated finite difference scheme”, for a two dimensional steady state incompressible viscous fluid flow has been proposed. The notable feature of the scheme is the incorporation of the local characteristics of the streamline at any node to discretise the stream derivative part of the vorticity-transport equation