GGU-3D-TRANSIENT: "Diffuse sources" menu item
Certain elements can be assigned time-dependent diffuse sources by defining the area required as a polygon using 4 anti-clockwise points. You will then see the following dialog box:

If diffuse sources have already been defined they can be deleted from the marked elements by pressing the "Delete" button. After clicking the "Assign" button a dialog box opens for assigning a polygon course. This menu item is required for simulation of a rainfall event, for example. During transient modelling the program first determines the time-dependent value for the polygon course and multiplies this with the element area. This is subsequently assigned as a source to the three nodes of an element. In the system visualisation, the FEM element is labelled with the polygon course number and additionally with an "f".