Crude estimate of velocity distributions from Truckenbrodt's energy and momentum coefficients



One of the simplest models for the velocity distribution in a pipe cross-section dependent on two parameters consists of two layers of different thickness and velocity. Unfortunately relative thickness and velocity of the wall layer cannot be expressed analytically in terms of Truckenbrodt's energy and momentum coefficents. But relative thicknesses of a three-layer model with wall and intermediate layer having opposite core and zero velocity can be. Reasonable in case of strong reverse wall flow only they allow a crude estimate of the parameters of the two-layer model, which may then serve as initial values in computing them iteratively. (© 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)