How convert file from CATIA to Gambit and ANSYS ?

[tuanshipland]

Hi all,

My name is Tuan Shipland, I am a Yacht Designer, my major is Naval Architecture and Marine Engineering.

My current project is including CFD (Gambit and Fluent - file.igs) and Structural Analysis (ANSYS - file.model or file.igs). And I design yacht in CATIA.

Shall we discuss about experience or knowledge in converting file from CATIA to Gambit and ANSYS?

I have some issues in meshing when I import file from CATIA to Gambit and ANSYS. Many surfaces are too complicated to mesh. Because they have many small edges in 3D model.

I am waiting for your reply!

Thanks for sharing your knowledge,

Share to development

Tuan Shipland

[bearflag]

Unless you have some serious processor capability and have the needs for aerospace level accuracy what you need to do is simplify your existing models keeping details where the critical areas are. Any places you can separate out or treat a as simpler system do that. This applies to meshing as well, we all want pretty hi resolution FEM meshes with thousands or hundreds of thousands or millions of cells and to reproduce exactly what we have in a complicated CAM type model but its better to take a step back and try to conceptualize what you actually are trying to accomplish with each model... instead of trying to solve the thousands of individual little things on the boat at the same time.

Sorry to say, but it can sometimes be a lot of work to do this simplification esp if you don't have the parametric files. Catia should allow you to "defeature" your models to the relevant things for your model. Once you get it into ANSYS you don't have the same level of control.

[tuanshipland]

Hi Bearflag,

As you said, I should simply my 3D model. Can you share how meshing in CATIA before importing into ANSYS? What steps should I do before importing model to ANSYS?

How diferent between meshing in ANSYS and CATIA? ANSYS I just know 2 method meshing that are "free meshing" and "map meshing". I know CATIA can meshing FE but I don't know how to do that, can you share me about this?

I have to make "Joint" tool (Generative Shap Design Module) in CATIA before importing my model into ANSYS for meshing. With simply model, it's OK. Besides, some complex model I have a problem that It has gap between surfaces so I cannot "Joint" these surfaces.

I will come back soon,

Thanks for your reply,

Share to develop

Tuan Shipland

[bearflag]

I don't use Catia (I use NX).

I wasn't saying you should do your meshing in Catia, Ansys most likely has better meshing tools.

BUt your model simplifying should be done there.

If your model is a Catia part file and has full history, simplifying could be fairly easy to very tedious. If your part doesn't have history... well.. it will be somewhat tedious ranging from reconstructing a simplified model from existing surfaces and solids to completely remodeling more primitive shapes.

In Ansys you will have lots of meshing options, you should be able to define various spaces as needing more detail and others less etc. Its not uncommon to have to import a model from CAD into CAE and have to send it back for changes before you get a workable mesh.

When I was back in university I spent weeks on some ridiculously simple models trying to get the meshes to be appropriate for the behavior I was trying to model. Tools are a lot better now, but its more of a black art rather than a pure technical endeavor to get your setup doing what it is supposed to.

[b1ck0]

Well ... you can import CATIA V4/V5 graphics to Gambit directly.

[tuanshipland]

Originally Posted by b1ck0

Well ... you can import CATIA V4/V5 graphics to Gambit directly.

Yes, I can import CATIA to Gambit. However, my model has some issues after I had imported it to ANSYS and GAMBIT. I cannot mesh it. Anyway, I thank you for you reply.

@bearflag: Thanks for your replies. Now I can solve it. I can import my model with .igs and .model.