  A novel centrifuge set-up for the study of unsaturated flow characteristics
in porous media is examined. In this set-up, simple boundary conditions can be
used, but a free moving boundary between unsaturated-saturated flow arises. A
precise and numerically efficient approximation is presented for the
mathematical model based on Richards' nonlinear and degenerate equation
expressed in terms of effective saturation using the Van Genuchten-Mualem
ansatz for the soil parameters in the unsaturated zone. Sensitivity of the
measurable quantities (rotational moment, center of gravity and time period to
achieve quasi steady state) on the soil parameters is investigated in several
numerical experiments. They show that the set-up is suitable for the
determination of the soil parameters via the solution of an inverse problem in
an iterative way, excluding the saturated hydraulic conductivity. For this
parameter, an existing simple centrifuge set-up is repeated and augmented with
transient measurements.
