FE-LM2
The FEFLOW modeling system incorporates a number of constitutive relations such as saturation vs. pressure and hydraulic conductivity vs. saturation for unsaturated flow or absorption isotherms and reaction kinetics for reactive transport. Various parametric expressions are provided in FEFLOW to describe these constitutive relations. It remains for the user to select the best suitable expression and to identify the respective parameter set. The parameter fitting tool FE-LM2 was designed to assist in this task, typically known as "curve-fitting."
Built around a Levenberg-Marquardt Local Minimizer, FE-LM2 provides instantaneous graphical feedback of a best fit when switching between parametric models and during user-controlled gradual changes in the weighting of selected data points. Possible local minima in the optimization function can be immediately recognized and subsequently circumvented by modifying the parameter ranges and optimization starting values through the user interface. As a parameter is gradually changed or explicitly set via the interface controls, the displayed shape of the corresponding model curve continuously tracks the user input.
Coupled models that share parameters can be fitted simultaneously to their respective data sets with graphical feedback provided for each set. The catalogue of parametric models provided in FE-LM2 includes all those implemented in FEFLOW.
FE-LM2 is only available on Windows systems.