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-   -   face splitting (http://www.cfd-online.com/Forums/fluent/27472-face-splitting.html)

Althea February 1, 2000 10:53

face splitting
 
Hello any Gambit gurus out there.

Does anyone else have problems using virtual face splitting in Gambit. Fluent are very vague about whether it works or not and generally advise me to use another (more time consuming and awkward) method.

Whenever I try to use it (either using edges or vertices) I get Error 6230 Sorry, the requested functionality has not been implemented yet.

I'm using the latest version of Gambit 1.2.0 and am developing strong views about people who include teasers in their codes for functions which are not implemented.

Regards Althea

John C. Chien February 1, 2000 14:04

Re: face splitting
 
(1). Obviously, the function is still under construction, based on your sympton. (2). I do have a very creative answer for you. If you keeps asking for new and better features in the program, and if they keep spending research money on it, their profit will drop, and then, they have to cut cost. After that, they will have no one to work on your new features. (3). So, unless you can convince them that your new features will bring new sale and that it can cover the cost and bring in more profit, then your request of new features will be waiting in the queue. (4). The problem is that CFD is a very specialized field. One can not compare it with the CAD or the spread sheet programs. So, this is my creative answer, which is always on the wrong side.

Aaron J. Bird February 1, 2000 21:45

Re: face splitting
 
I have had similar difficulties with face splitting so I've mostly just plugged and chugged at it the old way. To be honest, I've taken great pains and time to avoid virtual anything in Gambit because I always find myself -at some late stage in the decomposition- in need of boolean capabilities. Like you, I was also under the impression that these functions would be available in the newer version for use with virtuals, but I haven't been able to get them to comply yet...

Althea February 2, 2000 07:46

Re: face splitting
 
Although you haven't helped, your words have provided some comfort.

I did the advanced Gambit training in December. There I was encouraged to use virtual geometry and not avoid it at all costs as I had done previously. This is the first time I have given in to virtual geometry at a relatively early stage and you are right, I'm regretting it. Unfortunately I had no choice this time because the basic geometry came in as IGES data from Catia. The faces are never connected so cannot be used to create real volumes and the geometry is too complex to delete the faces and recreate them properly (which is what I normally do).

I have spent a whole day trying to find a work around to the face splitting problem. Including trying to recreate the faces, but due to the shape, nothing has worked. I will just refer back to what Jonas said about using Gambit when this user group first started. Then go and cry into my coffee.

Best wishes to all weary Gambit users.

Althea.

Jonas Larsson February 2, 2000 08:45

Re: face splitting
 
Did you try to import your IGES model with the new translator from Spatial? This will give you only real objects. You might then be able to "heal" the parts together. I've managed to import quite complicated IGES models into "real" gambit objects in this way, but I've also failed a few times so YMMW.

I agree with you that working with virtual geometry is a pain. I avoid it as long as possible.

Aaron J. Bird February 2, 2000 09:56

Re: face splitting
 
No need to give up just yet Althea... while crying in one's coffee is a good release temporarily, you can accomplish much in a few days or a week. I have been importing IGES files from 3-D scans and none of them have maintained consistent faces from the scan to Gambit, so I've just had to rebuild edges, faces, and volumes until I can get nice meshes. You may also consider cutting out parts of your geometry and saving them separately so you can work on theses pieces individually -i.e. not have the other parts of the geometry there on the screen to remind you they also need "rebuilt"- and then reassemble them when you are finished. Chin up! Good luck!

Kai Kang February 2, 2000 12:22

Re: face splitting
 
Those virtual geometry was really confusing for me at first, and I agree with you on its limitations, 'cause you can't do much once gone virtual...

I am just hoping Fluent can provide a magic button with one click I can get rid of all the virtual things and change my volume decomposition.

But now, I usually save the geometry as a separate dbs before going virtual, so that I could always come back to my model in case something was wrong.

Shyam Kishor February 2, 2000 13:16

Re: face splitting
 
Virtual face split works but the option of specifying a "Tolerance" by an user has not been implemented as yet. For now, you should not activate this option "tolerance" on the virtual face split form.

Gambit 1.2 does provide feature to convert non real(virtual/faceted) geometry to real geometry with some limitations. You should contact your support engineer for details.

Jurek February 2, 2000 18:56

Re: face splitting
 
I have the same problem. It never worked. But as the other say: do never become virtual ! Perhaps you can construct complicated edges in a cad-tool and import it seperate into gambit.


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