Poiseuille flow of purely viscous non-Newtonian fluids through ducts of non-circular cross section

In this paper, the relationships are presented for an approximate calculation of pressure drop–flow rate dependence and maximum fluid velocity in Poiseuille flow of power-law and Robertson–Stiff fluids through ducts of noncircular cross section. The suitability of the relationships derived is demonstrated by the comparison of calculated data of pressure drop and maximum fluid velocity with those taken from literature for various duct geometries.