Mesh Lines and confirming cumulative boundary flux rates
Mesh Lines and confirming cumulative boundary flux rates
Jirka and Mirek,
Thanks in advance and apologies for asking a question that probably has been asked and answered many times.
I'm interested in applying unit gradient boundary conditions at multiple locations and I'm wondering if there is a way to separate flux rates at the boundary. I'm simulating a lysimeter with lateral drainage measurements and deep percolation measurements.
I've tried using meshlines at each boundary location  however  I have noticed other users and Jirka has replied that meshlines are calculated with less precision than boundary conditions. I also recall that boundary condition types (free drainage  seepage faces  etc.) cannot be calculated separately, even if multiple conditions exist.
I'm hopeful you have suggestions for creative solutions to this problem and/or can correct my misconception. For the record, WatBalR is low at approximately 0.3%.
Again  thanks for your time.
Alex
Thanks in advance and apologies for asking a question that probably has been asked and answered many times.
I'm interested in applying unit gradient boundary conditions at multiple locations and I'm wondering if there is a way to separate flux rates at the boundary. I'm simulating a lysimeter with lateral drainage measurements and deep percolation measurements.
I've tried using meshlines at each boundary location  however  I have noticed other users and Jirka has replied that meshlines are calculated with less precision than boundary conditions. I also recall that boundary condition types (free drainage  seepage faces  etc.) cannot be calculated separately, even if multiple conditions exist.
I'm hopeful you have suggestions for creative solutions to this problem and/or can correct my misconception. For the record, WatBalR is low at approximately 0.3%.
Again  thanks for your time.
Alex
Re: Mesh Lines and confirming cumulative boundary flux rates
First, I think you can use meshlines for this (especially if you want to have both actual and cumulative fluxes). I do not think that the fluxes across meshlines are calculated with less precision. The same approach is used for those calculations as for calculations of boundary fluxes. You can define up to four meshlines.
Second, in the Boundary.out file, you can find nodal fluxes for all boundary nodes at a particular print time. If you add fluxes for selected nodes, you should get your actual boundary flux. However, in this way you will not get the cumulative flux.
J.
Second, in the Boundary.out file, you can find nodal fluxes for all boundary nodes at a particular print time. If you add fluxes for selected nodes, you should get your actual boundary flux. However, in this way you will not get the cumulative flux.
J.
Re: Mesh Lines and confirming cumulative boundary flux rates
Thanks for the reply Jirka.
Re: Mesh Lines and confirming cumulative boundary flux rates
Hi dear Jirka,
Is there a difference between tracing the meshline horizontally from left to right and from right to left ?
Is there a difference between tracing the meshline horizontally from left to right and from right to left ?
Re: Mesh Lines and confirming cumulative boundary flux rates
Meshlines are oriented depending on how you define them. The fluxes should be the same and independent of orientation except for the sign (+/). J.
Re: Mesh Lines and confirming cumulative boundary flux rates
ok very well thank you. I have to do 05 meshline and the whole thing does not work in the same. When I change the third mesheline in another direction it works. But this does not suit me in the rest because I do have sign problems.
Re: Mesh Lines and confirming cumulative boundary flux rates
I do not see why that would be a problem. If you reverse the points defining the meshline, you change the sign (although I do not see why you would do that). J.
Re: Mesh Lines and confirming cumulative boundary flux rates
Good evening Mr. Jirka
In my modeling, I have 05 mesh lines. Qunad I run the simulation with the 05 mesh lines, an error is displayed.
But when I delete the fourth mesh line the calculation is done correctly.
Thank you
In my modeling, I have 05 mesh lines. Qunad I run the simulation with the 05 mesh lines, an error is displayed.
But when I delete the fourth mesh line the calculation is done correctly.
Thank you
Re: Mesh Lines and confirming cumulative boundary flux rates
Indeed, there seems to be an error in GUI when 5 or more meshlines are used. The program works well when there are up to 4 meshlines. We need to check this bug. Sorry for that. In the meantime, use only up to 4 meshlines. J.
Re: Mesh Lines and confirming cumulative boundary flux rates
This error has been fixed. New installation programs Hydrus3D_3.02.0520_x86.exe and Hydrus3D_3.02.0530_x64.exe are available in ELIS.
Re: Mesh Lines and confirming cumulative boundary flux rates
Thank you all for your different answers.
I have attached an image of the error message.
Maybe this will bring a lot of clarity. I use version 2.04 of hydrus.
Mr. Mirek means ELIS
I have attached an image of the error message.
Maybe this will bring a lot of clarity. I use version 2.04 of hydrus.
Mr. Mirek means ELIS
 Attachments

 Nouveau document 20191218 13.44.07_1.jpg (958.66 KiB) Viewed 2184 times
Re: Mesh Lines and confirming cumulative boundary flux rates
I should clarify. I found a bug in Version 3.02, and that is the bug Mirek fixed. I have not seen the error in version 2.05. I do not have anymore the version 2.04. J.
Re: Mesh Lines and confirming cumulative boundary flux rates
Yes, this error was only fixed in the latest version of HYDRUS (which is 3.02.xxxx). HYDRUS 2.x is no longer maintained.
Re: Mesh Lines and confirming cumulative boundary flux rates
I have tested both version 2.04 and 2.05 with more than 6 meshlines, and with 3 solutes, and the code was working fine for me. J.
Re: Mesh Lines and confirming cumulative boundary flux rates
Hello Jirka and Mirek,
I think I understand the source of the problem. I have five models (lysimeter in a cell). The first four works. The five cases are differentiated by the dimensions of the lysimeter. The fifth case has the largest lysimeter. I think it doesn’t work because of the amount of data.
Is the finding made a possibility?
Thank.
I think I understand the source of the problem. I have five models (lysimeter in a cell). The first four works. The five cases are differentiated by the dimensions of the lysimeter. The fifth case has the largest lysimeter. I think it doesn’t work because of the amount of data.
Is the finding made a possibility?
Thank.
Last edited by Otthman on Thu Jan 16, 2020 3:57 pm, edited 1 time in total.