Apologies for asking the obvious:

1) When one programs in C there is the so-called ANSI standard. Sticking to this standard has obvious advantages. When commercial CFD codes or any other code for that matter makes use of unstructured grids or these grids are generated by the code are there also standards that are adhered to? In other words; do every CFD code developer decide in which way to store the grid node and connectivity information or is there a standard way to do this?

2)I have noted a number of open source code CFD programs but for structured meshes only. Is there a open source, unstructured CFD code out there? If so, is it useful to back-engineer this code or should one rather write an own code? Note that this is mainly for academic purposes, I am not really interested in competing with the commercial codes or even trying to solve specific flow problems. The idea is to have something with which to check out new ideas.

Can you show me some CFD source code about 3D modeling? please send web_link or zip files to my mailbox. Thank you!

Can you show me some CFD source code about 3D modeling? please send web_link or zip files to my mailbox. Thank you!

The closest thing to a standard method for storing both structured and unstructured CFD data is CGNS (www.cgns.org), but this addresses how to put things out in a more or less standard way - it does not tell you how to store your data internally.

I have never heard of any open source unstructured mesh code.

If you're looking for grid gen codes try http://capella.Colorado.EDU/~laney/softgrid.htm there are some unstructured (2d) grid gen codes there that you can look over. I am familiar with BAMG code from INRIA in France which is a very simple 2-D code. I don't know what sort of complexity level you were looking for. EMC2 (also developed INRIA) at http://www-rocq.inria.fr/gamma/cdrom/www/emc2/eng.htm is a more full feature gui based 2-d grid generator. Both generate grids in a simple to understand file format.

One could consider the unstructured grid file format used in Tecplot (consult a manual) as open format. Also some of the popular FEM formats like ANSYS, GRAPE PATRAN would quite like be described in their literature so that you can write codes that generate or accept their file formats.

I need a copy of it too ,please reform me if somebody has. I need it to finish my thesis.

thanks in advance.