  We study the behavior of the pulse waves of water into a flexible tube for
application to blood flow simulations. In pulse waves both fluid friction and
wall viscosity are damping factors, and difficult to evaluate separately. In
this paper, the coefficients of fluid friction and wall viscosity are estimated
by fitting a nonlinear 1D flow model to experimental data. In the experimental
setup, a distensible tube is connected to a piston pump at one end and closed
at another end. The pressure and wall displacements are measured
simultaneously. A good agreement between model predictions and experiments was
achieved. For amplitude decrease, the effect of wall viscosity on the pulse
wave has been shown as important as that of fluid viscosity.
