In the file sitr all material-specific parameters, stop criterion, scaling factors of node-and element values as well as information about the equation solver are stored, which are set through the input window of the calculation modules. The file is automatically created after starting the calculation module SITRA (or INSTAT) in the current working directory. It will initially contain the default settings matching the model type.

After editing the parameters in the dialog box, saving the batch file by pressing the button (file save as…) or starting the calculation with OK the changed parameters are stored in the sitr file. Due to the complex structure of the sitr file, it is not recommended to edit the file using a text editor.

( Crosslinking of water systems with file sitra_vsys.txt