[zuheyr]

Dear colleagues,



Using ICEM CFD 2020 R1 how can I write out Gambit input file ascii .neu. Unfortunately the solver I am using is using this format. I will greatly appreciate any help.



Thank you for reading.

[aero_head]

Originally Posted by zuheyr

Dear colleagues,



Using ICEM CFD 2020 R1 how can I write out Gambit input file ascii .neu. Unfortunately the solver I am using is using this format. I will greatly appreciate any help.



Thank you for reading.

Hello,

A direct conversion is no longer possible. From this thread: Converting Fluent mesh files to Gambit neutral files :

Now that Ansys no longer supports Gambit (after this month), it is no longer possible to export meshes in Gambit neutral format (*.neu) for any legacy codes which require it. Attached to this post is the code for two tools:

msh2neu: convert Fluent mesh files (*.msh) to Gambit neutral files (*.neu)
neu2msh: convert Gambit neutral files (*.neu) to Fluent mesh files (*.msh)

The code is limited to two dimensional, non-periodic meshes. However, it supports tagging of boundaries (for specification of boundary conditions in your code) and tagging of mesh regions (e.g. to distinguish an outlet region where the convection-diffusion equation is solved instead of Navier-Stokes).

Compilation is using gcc and make. Also included is documentation. I could not include any example meshes or icemcfd projects because of the size constraint on attachments.

[zuheyr]

Dear Kira,

I very much appreciated this. Thank you. Please allow me to tell you my success and failure. Very best wishes and kindest regards!
Zuheyr

[zuheyr]

Dear Kira,

I come back to you for the converter from .msh to .neu.

I am using your program and I am grateful. The program that I need to run crashes however, and I discovered that your program has the boundary condition list and element number whereas the code requires boundary condition and the element list has 2 integers appended to each element, viz:


From the .neu file that runs
BOUNDARY CONDITIONS 2.4.6
Symmetry 1 165 0 6
930 2 3
928 2 3
927 2 3
926 2 3

.....



The one from you: (not the same case, I do not have gambit)


BOUNDARY CONDITIONS 2.2.30
SYMMETRY 0 49 0 24
1025
2
.......



From the .neu file format reference:
https://web.stanford.edu/class/me469...mbit_write.pdf


Boundary Conditions Sets (Optional)
This section identifies and labels points, edges, and/or faces to which boundary conditions are to be applied. Each set of boundary conditions is preceded
by a header and control record.

There are two types of boundary-condition sets. One provides a list of grid
points; the other provides a list of element/cell faces.



Would you have any idea if I can write out this data from your code?


Many thanks and kindest regards, Zuheyr

[aero_head]

Originally Posted by zuheyr

Dear Kira,

I come back to you for the converter from .msh to .neu.

I am using your program and I am grateful. The program that I need to run crashes however, and I discovered that your program has the boundary condition list and element number whereas the code requires boundary condition and the element list has 2 integers appended to each element, viz:


From the .neu file that runs
BOUNDARY CONDITIONS 2.4.6
Symmetry 1 165 0 6
930 2 3
928 2 3
927 2 3
926 2 3

.....



The one from you: (not the same case, I do not have gambit)


BOUNDARY CONDITIONS 2.2.30
SYMMETRY 0 49 0 24
1025
2
.......



From the .neu file format reference:
https://web.stanford.edu/class/me469...mbit_write.pdf


Boundary Conditions Sets (Optional)
This section identifies and labels points, edges, and/or faces to which boundary conditions are to be applied. Each set of boundary conditions is preceded
by a header and control record.

There are two types of boundary-condition sets. One provides a list of grid
points; the other provides a list of element/cell faces.



Would you have any idea if I can write out this data from your code?


Many thanks and kindest regards, Zuheyr

Hello Zuheyr,

Sorry to hear you are having this issue. Have you tried anything, and if so, what? Maybe we can work from there.

[zuheyr]

Originally Posted by aero_head

Hello Zuheyr,

Sorry to hear you are having this issue. Have you tried anything, and if so, what? Maybe we can work from there.

Dear Kira,

Thank you so very much. As long as I cannot show you the .neu file that works and the neu file created with your tool are not available, I do not have GAMBIT, attaching files will not help.

My problem is: only the list of the boundary elements are listed by your conversion program but the solver I am using needs 2 other numbers which seem to be present in Gambit written .neu files as I had written in my previous post above from the .neu file description.


Just briefly:

This is what your code writes:
BOUNDARY CONDITIONS 2.2.30
Symmetry 0 49 0 24
1025
..... (deleted)

This is what the code needs:

BOUNDARY CONDITIONS 2.4.6
Symmetry 1 164 0 6
1025 2 1
..... (deleted)


I also discovered in the original post that you referred to, someone replied that there was no connectivity information in the coversion process. The actual author replied to that post saying that he cannot offer any further asistance.

Please tell me if you want me to attach a small test prj files, or the msh file?

Many sincere thanks, Zuheyr

[bluebase]

Hi Zuheyr,


your problem seems to require significant amount of work. Aero_head gave you already valuable starting points.


I believe, it might not be very likely to find someone having a ready solution. The most likely are other people using your solver. They sure had the same problem, wouldn't they? Look for them.



If that's a dead end, it is likely up to yourself to program a next version of msh2neu - custom solver means custom work =|

If there are funds, you might hire someone to develop such a converter...

[zuheyr]

Originally Posted by bluebase

Hi Zuheyr,


your problem seems to require significant amount of work. Aero_head gave you already valuable starting points.


I believe, it might not be very likely to find someone having a ready solution. The most likely are other people using your solver. They sure had the same problem, wouldn't they? Look for them.



If that's a dead end, it is likely up to yourself to program a next version of msh2neu - custom solver means custom work =|

If there are funds, you might hire someone to develop such a converter...

Thank you so much!


Well I hope you are not the boss of Kira because I have replied his/her last post. I am sure that the task is not gigantic and of interest to many people.



All one needs is a good description of the Gambit neutral file format and that is it.



So, if necessary, I would ask your kind permission to continue the thread.


Best,
Zuheyr

[bluebase]

Originally Posted by zuheyr

Well I hope you are not the boss of Kira because I have replied his/her last post.

Don't jump to conclusions.

I just wanted to reference a post in this thread by the author's alias.

So, if necessary, I would ask your kind permission to continue the thread.

I am no authority on that.

I am sure that the task is not gigantic and of interest to many people.
All one needs is a good description of the Gambit neutral file format and that is it.

Let's hope that.



My intention was to adjust your expectations from my point of view. Feel free to consider it as-is - an opinion.