Retention Curve Hysteresis of Capillary Barrier

Abstract:

To obtain parameters of the applied model, just the drying branches
of retention curves of the utilized materials are usually measured.
Recent studies show that, especially in the case of the capillary
layer, this approach overestimates the capillary barrier's efficiency.
Hence, the reliability of the model can be improved when measuring
both, the drying and the wetting, branches and including hysteresis
to the model.

In the reported research, the retention data and saturated hydraulic
conductivities were measured on samples in a laboratory. The main
drying and the main wetting branches were measured on all samples.
The Havlicek and Myslivec type of tension apparatus was utilized to
carry out the measurements. A model of hysteresis based on the scaling
approach was included into the mathematical model. The capillary
barrier was simulated numerically so that the comparison with results
of a standard model was enabled.

The submitted contribution presents the obtained results and their
discussion.