Dual porosity output file

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ahughes7
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Joined: Tue Dec 18, 2018 7:21 pm
Location: Canada

Dual porosity output file

Post by ahughes7 » Wed Dec 19, 2018 10:09 pm

Hello,

I am attempting to model some soil tension data using the dual porosity (head mass transfer). The output file Nod_Inf shows me the water contents for both mobile and immobile fractions with depth and only heads for the mobile portion (i.e. macropores). I am comparing this output to measured heads in the matrix. Is there any way to get "immobile head" outputs (i.e. matrix heads) instead of just immobile water content?

Thanks!

Alex

Jirka
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Location: USA
Location: Riverside, CA

Re: Dual porosity output file

Post by Jirka » Wed Dec 19, 2018 10:39 pm

The pressure head in the immobile zone is defined only when you use the "Dual-Porosity model with the Pressure Head Mass Transfer". It is not defined when you use the "Dual-Porosity model with the Water Content Mass Transfer". In the former case you should be able to calculate the pressure head in the immobile zone from the immobile water content and soil hydraulic parameters for the immobile zone. J.

ahughes7
Posts: 8
Joined: Tue Dec 18, 2018 7:21 pm
Location: Canada

Re: Dual porosity output file

Post by ahughes7 » Wed Dec 19, 2018 11:22 pm

Thanks for the speedy response! Does that mean that when doing the inverse solution, if I input pressure heads as data, the model assumes these are from the immobile zone?

Thanks

Alex

Jirka
Posts: 5268
Joined: Sat Mar 16, 2002 3:47 pm
Location: USA
Location: Riverside, CA

Re: Dual porosity output file

Post by Jirka » Wed Dec 19, 2018 11:36 pm

From the mobile zone. J.

ahughes7
Posts: 8
Joined: Tue Dec 18, 2018 7:21 pm
Location: Canada

Re: Dual porosity output file

Post by ahughes7 » Thu Dec 20, 2018 12:08 am

Right, that's what I meant. Thank you!

Jirka
Posts: 5268
Joined: Sat Mar 16, 2002 3:47 pm
Location: USA
Location: Riverside, CA

Re: Dual porosity output file

Post by Jirka » Thu Dec 20, 2018 2:23 am

I figured. But I had to corrected it as the forum is public. J.

ahughes7
Posts: 8
Joined: Tue Dec 18, 2018 7:21 pm
Location: Canada

Re: Dual porosity output file

Post by ahughes7 » Tue Jan 22, 2019 8:31 pm

Hello again,

With regards to my previous question, can you explain why the model outputs water contents in the immobile region that are higher than the specified theta_s values? For example, in the dual-porosity model (head mass transfer) I have specified theta_s for the mobile fraction (0.11) and the immobile fraction (0.32) for a theta_total of 0.43. But the model is reporting water contents of 0.35 for the mobile and 0.31 for the immobile at the same node for the same timestep.

Thanks,

Alex

Jirka
Posts: 5268
Joined: Sat Mar 16, 2002 3:47 pm
Location: USA
Location: Riverside, CA

Re: Dual porosity output file

Post by Jirka » Fri Jan 25, 2019 6:09 pm

I have never seen it happening. Can you post your project here? J

ahughes7
Posts: 8
Joined: Tue Dec 18, 2018 7:21 pm
Location: Canada

Re: Dual porosity output file

Post by ahughes7 » Fri Jan 25, 2019 11:05 pm

Hello, I was able to fix the issue by increasing the percentage of mobile domain (i.e. by lowering theta_immobile and increasing theta_mobile, keeping theta_total the same). The original project is attached if you are still interested.
Cheers,
Alex
Attachments
F8_calibration_1.zip
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