The two-dimensional effect of plasma flow along the field lines in the scrape-off zone of a poloidal divertor has been modelled phenomenologically in a one-dimensional tokamak transport code. Some results for the density and temperature profiles in the scrape-off zone, as well as in the main plasma, are given in this paper. These calculations suggest some approximations, which have been used to develop a zero dimensional model of the divertor; this model can be used to make estimates of divertor performance without having to make detailed numerical calculations.