Recent investigations of problems associated with the Hagen-Poiseuille flow law

Attention is drawn to the fact that the Hagen-Poiseuille law is valid only for the elementary case of Newtonian fluids in a circular cylindrical channel. All other cases are currently treated by means of unreliable approximate formulas. In the present paper, contemporary geometrical and analytical considerations are used to devise a modification of the H-P law that provides a much improved treatment of problems involving fluids of various types in channels of various cross sectional configurations.