Paper presented at the 8th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Mauritius, 11-13 July, 2011.
The main goal of the developed theory is to formulate the
biomechanical conditions (geometrical dimensions, viscoelastic
properties of veins and blood fluid flow conditions) at which an
unstable behavior or even the vein collapse can occur. The
above problems are numerically modeled by the finite element
method. The weak formulation of the tube deformation is based
on the virtual work principle. The mixed formulation of the
finite element method with the separately interpolated pressure
is used for the structure. The strong coupling of both structure
and fluid solvers allow us to simulate self-induced large
deflection oscillations of the tube.
Provided that the Neo-Hook’s material model was applied
the analytical formula for the collapse conditions was found. It
was proved that for the brain vein contraction about 5%, the
vein collapse can occurs even under normal physiological
condition – the angiosynizesis.
The fluid structure interaction is studied experimentally on
the special experimental line. The fluid structure phenomenon
is investigated both for the continuous and pulsating flow and it
is evaluated by a non-invasive optical. The method is based on
optical measurements of radial displacement of the pulsating
tube wall.
The simultaneous clinics observation (histological findings),
in vitro experiments and numerical modeling gives sufficient
data to predict biomechanical conditions of the angiosynizesis.
