Immobile water content and residual water content

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thotran11292
Posts: 15
Joined: Fri Jun 17, 2022 2:13 am
Location: Korea

Immobile water content and residual water content

Post by thotran11292 » Tue Jan 09, 2024 6:27 am

Dear all,

I am using an inverse Mobile and Imobile water model in HYDRUS 1-D. I forced HYDRUS to calculate theta_r and theta_im.

Is there any relationship or correlation between these two? Should theta_r be less than theta_im? Indeed, they are two different concepts but not so sure about their relationship.

Thank you.

Best regards

Jirka
Posts: 6253
Joined: Sat Mar 16, 2002 3:47 pm
Location: USA
Location: Riverside, CA

Re: Immobile water content and residual water content

Post by Jirka » Tue Jan 09, 2024 6:55 pm

H1D does not consider any relationships or correlations between theta_r and theta_im. Theta_r does not have to be less than or equal theta_im. However, if theta_im is larger than theta_r, in transient simulations, you may encounter unphysical situations when theta_im is larger than theta (which would result in infinite fluxes). Thus, theta_im must be smaller than the smallest theta during the entire simulation. J.

thotran11292
Posts: 15
Joined: Fri Jun 17, 2022 2:13 am
Location: Korea

Re: Immobile water content and residual water content

Post by thotran11292 » Wed Jan 10, 2024 3:49 am

Dear Jirka,

Thank you so much for your reply.

Best regards

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