A partially saturated calculation can be carried out for vertical or 3D models.

With SITRA, this is carried out using the pressure-saturation functions or the function using the relative K value according to van Genuchten.

Three parameter sets are preset in SITRA for the variables residual saturation (Sres), reciprocal value of the water inlet pressure (a), pore size index (n) and specific parameter of the relative K-value function (l), which are automatically assigned to the corresponding soil types and van Genuchten parameters by the order of magnitude of the K-value present in the model. The exact assignment can be found in the table in the description of the model data.

Calculation with van Genuchten-functions