Experiments of draining and filling processes in a collapsible tube at high external pressure

¹ Matière et Systèmes Complexes, MSC UMR 7057, Université Paris 7, 75013 Paris, France
² Boston Scientific, France
³ UPMC Univ Paris 06, UMR 7190, Institut Jean Le Rond d’Alembert, 75005 Paris, France
⁴ CNRS, UMR 7190, Institut Jean Le Rond d’Alembert, 75005 Paris, France

^a e-mail: jose.fullana@upmc.fr

Received: 26 May 2011
Revised: 26 October 2011
Accepted: 25 January 2012
Published online: 23 February 2012

Abstract

The venous circulation in the lower limb is mainly controlled by the muscular action of the calf. To study the mechanisms governing the venous draining and filling process in such a situation, an experimental setup, composed by a collapsible tube under external pressure, has been built. A valve preventing back flows is inserted at the bottom of the tube and allows to model two different configurations: physiological when the fluid flow is uni-directional and pathological when the fluid flows in both directions. Pressure and flow rate measurements are carried out at the inlet and outlet of the tube and an original optical device with three cameras is proposed to measure the instantaneous cross-sectional area. The experimental results (draining and filling with physiological or pathological valves) are confronted to a simple one-dimensional numerical model which completes the physical interpretation. One major observation is that the muscular contraction induces a fast emptying phase followed by a slow one controlled by viscous effects, and that a defect of the valve decreases, as expected, the ejected volume.