Fig 3. The effective water film thickness of the rough surface domain as a single patch for different hydration conditions (expressed by the matric potential of the aqueous phase).
The surface porosity scales effective water film thickness when the fractal dimension is constant D = 1.4 (Dp = 2.4). When the surface porosity (Φ = 0.1) is low the model agrees with the experimental data of [97]. Here, we set the largest roughness element size rmax = 50 mm as a possible representation of the surface depression of the sample rock used in the experiment [97].