Add innactive cells to Local Grid Refinement

[laura-del-val-Eurecat]

Hi Everyone!

I have a question: I'm trying to generate a grid using the LGR utility, but I don't know in which grid (the parent or the child) and how (giving 1 or 0 value) should I specify the inactive cells. This is a model of a catchment (so it is NOT rectangular ) were cells around the catchment limits should be inactive.

Thank you in advance for the help. Cheers!!

[langevin-usgs]

Hello @laura-del-val-Eurecat, there is some documentation here, which you have probably seen already. The idea is that you create an indicator array for the parent grid. In the example, this array is called idomainp. This array should have a 1 everywhere except for cells that you want to be represented with the child grid. This indicator array is then passed to to the Lgr utility. In your case you also want to deactivate other parts of the model in order to follow the boundary of your area of interest. You will need to do that as a separate option after you have used the Lgr utility.

In the example, the line below creates the discretization package for the parent model:

dis = flopy.mf6.ModflowGwfdis(gwfp, **lgrp.get_gridprops_dis6())

You'll need to modify that and instead pass in an idomain (shown below as myidomainarray) that you create, which has 0's in the area for the child grid and also 0's in the inactive part of your model domain. The trick for you will be figuring out how to create myidomainarray, which hopefully can be done using flopy intersect utilities or something else.

dis_dict = lgrp.get_gridprops_dis6()
dis_dict["idomain"] = myidomainarray
dis = flopy.mf6.ModflowGwfdis(gwfp, )

Hopefully this can help keep you moving.