CFD Online Discussion Forums

CFD Online Discussion Forums (
-   Phoenics (
-   -   CAD objects to PHOENICS (

bathman January 20, 2003 03:28

CAD objects to PHOENICS
I need help about this. Can CAD objects be imported to PHOENICS? Will the air velocity profile follow the contours of this CAD object? Sometimes, it appears as passing through a block. Thanks.

cham January 20, 2003 05:47

Re: CAD objects to PHOENICS
CAD objects can be imported into the VR Editor. The recommended CAD file format is a non-binary STL file. DXF files

From memory it is possible to save solid shapes in non-binary STL format from AutoCAD as follows:

(a) create a 3D solid in the positive octant; (b) type the command STLOUT; (c) select the 3D solid to be exported; (d) answer NO to the question 'Binary?'; (e) name the file.

There have been problems in PHOENICS when importing CAD files using DXF format, which is why STL is preferred if possible. DXF format does not always define solid shapes directly (in the way that STL does) and so it is less reliable when used as the basis for CFD simulations around and within solid structures. Experience shows that, because of this, DXF files often contain errors: typically, faces are missing, or fail to join correctly, leading to ambiguous, or even impossible, configurations.

Leon Mills January 20, 2003 23:06

Re: CAD objects to PHOENICS

Also look at the grid around the object that you are importing.

If you are using VR-Viewer to define the grid I strongly recomend to set object effects grid to YES (ON) and refine the mesh around the object.

I also have used fine-mesh volume around particular areas of interest to refine the mesh.

Hope this helps.


Hans January 29, 2003 17:03

Re: CAD objects to PHOENICS
Does your block geometry complex? I had similar problem. What I did to avoid the problem was diving the block into simpler blocks.

All times are GMT -4. The time now is 23:13.