If the dye computational option is selected as shown in Figure 1 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 EFDCPlus 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 Table 1.
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.