Inverse determination of soil characteristics with a bench-scale centrifuge

We utilize a bench-scale centrifuge to speed up the process of porous media inltration. This allows to obtain measurements in a fraction of the time needed by standard inltration methods, especially for clayey soils. By measuring only transient data like water level in an inflow or outflow chamber, gravitational center of the sample, or the rotational momentum of the sample, it is possible to determine the soil characteristics. This is done by solving the inverse problem based on the mathematical model for saturated and unsaturated water infiltration in soil. The model for the unsaturated flow is based on Richards' equation and the Van Genuchten-Mualem formula. We present the experimental set-up, accuracy of the measurements, and the numerical solution method. For saturated flow we compare with standard tests and the classical formula for hydraulic conductivity in a centrifuge from two discrete measurements.We utilize a bench-scale centrifuge to speed up the process of porous media inltration. This allows to obtain measurements in a fraction of the time needed by standard inltration methods, especially for clayey soils. By measuring only transient data like water level in an inflow or outflow chamber, gravitational center of the sample, or the rotational momentum of the sample, it is possible to determine the soil characteristics. This is done by solving the inverse problem based on the mathematical model for saturated and unsaturated water infiltration in soil. The model for the unsaturated flow is based on Richards' equation and the Van Genuchten-Mualem formula. We present the experimental set-up, accuracy of the measurements, and the numerical solution method. For saturated flow we compare with standard tests and the classical formula for hydraulic conductivity in a centrifuge from two discrete measurements.C