Method for the evaluation of minor losses in pulsatile laminar fluid flow

CTU in Prague, Faculty of Mechanical Engineering, Department of Fluid Mechanics and Thermodynamics

^a Corresponding author: hana.netrebska@fs.cvut.cz

Published online: 25 March 2014

Abstract

This article focuses on description and evaluation of the size of the minor losses in pulsatile laminar flow. It describes a method for determination of minor losses with respect to the phase delay between pressure waveforms and flow waveforms. The whole evaluation method is presented on the example of minor loss in the sharp 90° bend in the channel with constant square cross-section in pulsatile laminar flow of an incompressible Newtonian fluid. For this example, the minor loss coefficient is expressed depending on the dimensionless flow parameters. Total minor loss was calculated numerically. An analytical solution was used for quantification of the head loss in the developed laminar flow in the straight channel. Unsteady flow conditions were controlled by the sinusoidal flow.