Mesh Generation
 

Hello Fluent users,

I am a new Fluent user and an old time CFX user and am trying to make the adjustments to a new code.

Is anyone out there writing their own meshes from scratch? I am looking at creating my own mesh in MATLAB and importing it into Fluent. I know this was easy and useful in CFX 4.4, but I imagine it will be more complicated in Fluent because of the unstructured code.

If anyone has any experience with this, do you have any comments on the ease and feasibility?

Jonathan

Re: Mesh Generation
 

Yeah, don't expect much help from fluent. I think after about 3 days of trying to write a mesh file that fluent could read, I had something that *didn't* crash fluent - although it still didn't actually work.

I think you need to have a long read of the relevant section of the manual, and then very carefully think about how you will create the data that is needed.

It is very easy to get confused.

Be patient

Rob

Re: Mesh Generation
 

May I ask why you are doing this? I'm just curious as to what type of exotic mesh you are trying to create that supposedly cannot be created in Gambit or ICEMcfd, for example. Or this just an exercise in coding?

Re: Mesh Generation
 

Well, it was partly an exercise in programming, but more because I thought it would be easier to express the geometry I wanted in my own program, than to struggle trying to explain it to Gambit.

When it comes down to it, I have 15 years of experience in programming, and only a few weeks (spread out over two years) with Gambit. It's not that I don't believe gambit could do it - in fact it is probably fairly easy for somebody who knows what they're doing. It's just for me, I am much more fluent in code.

Despite my earlier warning, it only took a few minutes to write the code that generated the nodal coordinates, it just took a long time to get my head around what was needed to tell fluent how to connect them all together. I suspect the problem was that my mesh was essentially "structured", but the fluent file-format is designed for "unstructured" and so needs a lot more information than I had designed my program to create.

I did spend a while looking for a "structured" file format that I could create more easily, and then import into either gambit or fluent, but docs for these sort of things seems to be thin on the ground.

Re: Mesh Generation
 

You could output your mesh in the GAMBIT neutral format, (which is described in detail in appendix C of the gambit user's guide) and then import this into fluent. I haven't tried it, but the information on the format is quite in depth. Good Luck

cheers, andrew

Re: Mesh Generation
 

hmm, my gambit user guide stops at Appendix B!!

Maybe it's time to upgrade? What version do you have?

Rob

Re: Mesh Generation
 

I echo Rob's reply. You just have a lot more control when you write your own mesh. It makes mesh refinement studies much simplier and the entire process can be completed more quickly.

And like I said this was very powerful and easy with structured code.

I will look at the Gambit Neutral Format. I was also looking at the Fidap Neutral Format. It looks like it might be a little more intuitive. Does anyone have any thoughts on that?

Jonathan

Re: Mesh Generation
 

Hi Rob, I have version 2.0.4, you can google for the users guide on the net

http://www.google.com/search?hl=en&i...f-8&c2coff=1&q=%22GAMBIT+USER%27S+GUIDE%22&spell=1

I think you have to use the second or third link down, or from the fluent users site

http://www.fluentusers.com/gambit2/doc/doc_f.htm

i hope this helps.

cheers andrew