Developing laminar flow in a pipe of circular cross-section

Abstract
A method is described of predicting flow development and pressure drop in the inlet of a uniform pipe of circular cross-section for the incompressible isothermal laminar flow of a Newtonian fluid. Employment of both the differential and integral momentum equations leads to greater simplicity of expression than is found in other theoretical treatments, though the solutions obtained compare equally favourably with the limited experimental measurements available; those reported herein suggest the need for a more generalized analytical approach which covers non-isothermal flow and the effect on flow development of temperature-dependent viscosity.