## Search found 13 matches

Fri Apr 05, 2024 1:21 am
Forum: HYDRUS (commercial version 1D,2D,3D)
Topic: Inverse Mobile-Immobile model and sensitivity analysis
Replies: 4
Views: 1176

### Re: Inverse Mobile-Immobile model and sensitivity analysis

Have a good day.
Thu Apr 04, 2024 4:57 am
Forum: HYDRUS (commercial version 1D,2D,3D)
Topic: Inverse Mobile-Immobile model and sensitivity analysis
Replies: 4
Views: 1176

### Re: Inverse Mobile-Immobile model and sensitivity analysis

Dear Jirka, Thank you so much for your reply. 1/With ML algorithm, with a certain initial guess, we might only get the local minimum, not the global one. That means if we tried different initial guesses and got different results, that means we have various local minimums, right? 2/Thank you for your...
Thu Apr 04, 2024 12:29 am
Forum: HYDRUS (commercial version 1D,2D,3D)
Topic: Inverse Mobile-Immobile model and sensitivity analysis
Replies: 4
Views: 1176

### Inverse Mobile-Immobile model and sensitivity analysis

Dear all, I am running the inverse mobile-immobile model for determining some parameters including (mass transfer between mobile and immobile water, and theta_immobile). as the nature of least square estimation, the model gives the best optimized results for those variables (as fas as I understand)....
Wed Jan 10, 2024 3:49 am
Forum: HYDRUS (commercial version 1D,2D,3D)
Topic: Immobile water content and residual water content
Replies: 2
Views: 8442

### Re: Immobile water content and residual water content

Dear Jirka,

Best regards
Tue Jan 09, 2024 6:27 am
Forum: HYDRUS (commercial version 1D,2D,3D)
Topic: Immobile water content and residual water content
Replies: 2
Views: 8442

### Immobile water content and residual water content

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 relat...
Fri Nov 03, 2023 6:28 am
Forum: Hydrus 1D (old free version)
Topic: Retardation factor in mobile and immobile water model
Replies: 2
Views: 17838

### Re: Retardation factor in mobile and immobile water model

Dear Jirka,

Have a good day~
Thu Oct 19, 2023 6:25 am
Forum: Hydrus 1D (old free version)
Topic: Retardation factor in mobile and immobile water model
Replies: 2
Views: 17838

### Retardation factor in mobile and immobile water model

Dear Jirka, I have one question not directly regards to HYDRUS 1-D. But I am using HYDRUS 1-D for inversely fitting model using Mobile-Immobile water model to obtain several parameters and aimed to calculate the retardation factor of solute. I crossed several manuscripts and found that we can calcul...
Thu Feb 02, 2023 1:53 am
Forum: Hydrus 1D (old free version)
Topic: Mobile-Immobile model
Replies: 10
Views: 7446

### Re: Mobile-Immobile model

Dear Jirka,

Thank you so much for your quick and helpful response. It does help me a lot.

Have a good day!

Best regards,

Tho Tran
Thu Feb 02, 2023 1:03 am
Forum: Hydrus 1D (old free version)
Topic: Mobile-Immobile model
Replies: 10
Views: 7446

### Re: Mobile-Immobile model

Dear Jirka, Thank you for your reply. It is very helpful. Can I have one more question please? Under such condition, when we consider the Freundlich absorption, there is a term of "Fraction of sorption site in contact with mobile zone" - known as f. I crossed several papers, some assumes that as the...
Wed Feb 01, 2023 7:40 am
Forum: Hydrus 1D (old free version)
Topic: Mobile-Immobile model
Replies: 10
Views: 7446

### Re: Mobile-Immobile model

Dear Jirka, I crossed by this post. and have one question please? "In the system with macropores, the dual-porosity model (which requires two domains – mobile and immobile) likely interprets the entire matrix as being immobile, since the flow is dominated by macropores." You stated this. Could you e...
Fri Dec 16, 2022 1:14 am
Forum: Hydrus 1D (old free version)
Topic: Dual porosity model with two-site sorption
Replies: 3
Views: 3149

### Re: Dual porosity model with two-site sorption

Dear sir, Thank you so much for your quick response. I got it now. I have one more question, please. The Dual-Permeability Model with the two-site sorption model is inactivated in my HYDRUS 1-D version (which I downloaded from PC-progress website). Could you tell me how to activate it or which versi...
Thu Dec 15, 2022 7:10 am
Forum: Hydrus 1D (old free version)
Topic: Dual porosity model with two-site sorption
Replies: 3
Views: 3149

### Dual porosity model with two-site sorption

Dear Sirs, I have two questions regarding to Chemical and Physical Nonequilibrium Models in HYDRUS 1-D. Currently, I only see the Dual-Porosity Model with two-site sorption in the Mobile zone in the HYDRUS 1-D version that I am using. The "Modeling Nonequilibrium Flow and Transport Processes using H...
Mon Oct 24, 2022 8:07 am
Forum: STANMOD
Topic: link between two-region and two-site model
Replies: 0
Views: 82811

### link between two-region and two-site model

Dear all, My study is about the transport of As(V) through the vadose zone. I conducted the tracer test (with Cl-) and found that the two-region physical nonequilibrium model fitted well. Normally people used the equilibrium model for the tracer test and then use fitted v and D for modeling reactive...