Eulerian and Lagrangian description of a pulsatile, partially turbulent flow

Abstract

A detailed flow field analysis is carried out downstream of a Bj6rk-Shiley prosthetic aortic valve, placed in a Great Circulation simulator. Mean periodic velocity and turbulence are obtained by means of selective sampling through enabling windows. Flow mapping includes three different heights and three meridional planes (i.e. nine diameters). Some effort is devoted to study cycle-to-cycle variations, and to remove them for determining true turbulence values. A lagrangian interpretation, based upon the convection of vorticity produced at the aortic prosthesis, is needed to understand the flow pattern behaviour.