Time-variable flux and variable head boundary use

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maxl
Posts: 2
Joined: Tue Apr 11, 2017 12:04 am
Location: Canada

Time-variable flux and variable head boundary use

Post by maxl » Tue Apr 11, 2017 4:58 pm

Hi,

I'm working on a problem where in one part of the domain ET can be represented as only having an evaporation component and in the other part of the domain I'm partitioning transpiration and evaporation based on LAI. The sides of my model are represented by variable head boundary conditions. At the surface on the part of the domain with only an evaporation component, I'm attempting to implement a variable flux boundary condition that is treated as atmospheric to capture where PET = potential evaporation. However, when I select the 'boundary condition option' to treat the variable flux as atmospheric, the variable heads seem to no longer be considered. Some further details:

-I've input the variable flux as 'variable flux 1'
-None of the variable heads are 'variable head 1' (because of the special treatment of variable flux 1 and variable head 1 under 'boundary condition options'

I've attached two rudimentary models that show the general problem, but I've excluded the part of the domain with transpiration. The two models show the difference based on whether the variable flux is not treated as atmospheric (the first file) or treated as atmospheric (the second file).

My apologies if I've missed something in the manuals, on this forum, or if this is not an option in Hydrus.
Thanks
Attachments
Var_boundarytest_runs.zip
(783.67 KiB) Downloaded 125 times

Jirka
Posts: 4712
Joined: Sat Mar 16, 2002 3:47 pm
Location: USA
Location: Riverside, CA

Re: Time-variable flux and variable head boundary use

Post by Jirka » Tue Apr 11, 2017 11:55 pm

Indeed, I have changed the code so that the option of treating time-variable flux as an atmospheric boundary is automatically applied to all four time-variable BCs. Since when these BCs are treated as atmospheric, the code switches between head and flux BCs, it is not possible o have at the same time also time-variable head BCs. I see that I need to do something about it. I need to think about it. J.

Jirka
Posts: 4712
Joined: Sat Mar 16, 2002 3:47 pm
Location: USA
Location: Riverside, CA

Re: Time-variable flux and variable head boundary use

Post by Jirka » Wed Apr 12, 2017 12:13 am

Try this code and let me know what you think. J.
Attachments
test_var_flux_var_head_2.zip
(972.99 KiB) Downloaded 150 times

maxl
Posts: 2
Joined: Tue Apr 11, 2017 12:04 am
Location: Canada

Re: Time-variable flux and variable head boundary use

Post by maxl » Fri Apr 14, 2017 2:42 am

This is excellent and did the trick. Much appreciated!

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