If the dye computational option is selected as shown in Dye_Age Tab then the user may assign a "decay" rate to the otherwise conservative tracer.
The "dye" constituent may also be used as an "age of water" function to compute residence times and visualize domain/boundary water mixing if this option is selected. This option is available in EFDC_DSI only.
See Apply Cell Properties via Polygons as to how to apply cell properties via polygons with the Dye button in the Initial Conditions frame.
Figure 1 Dye/Age Tab
The "decay" rate options are shown in Dye_Age Tab.
Table 1 Dye "decay" rate options.
Dye "Decay" Rate | EFDC_DSI Operation |
>0 | First order decay rate |
0 | Conservative tracer |
<0 | First order growth rate (EFDC_DSI Only) |
Depending on the decay rate option, the user can view and animate the dye concentrations or age of water in ViewPlan.
If using the restart option, the user can initialize a dye field using the DYE.INP file by selecting the Dye Overwrite check box on the Initial tab, located in the EFDC Restart Option frame.