Replacing or recreating STL/triangulated geometry for parameterization

[Joshua C 0]

Hello,

I'm brand new to CAESES so forgive me if this is an elementary topic. On the blog post talking about linking CONVERGE and CAESES (https://www.caeses.com/blog/2019/converge-cfd-software-full-automation-with-caeses/) there is a sentence saying "Users can then quickly replace the geometry parts that need variation or optimization [after importing their geometry from CONVERGE]."

I've imported my geometry from CONVERGE, which gives me a closed manifold (or watertight) geometry. I have some holes in this geometry that I want to parameterize by changing the number and size of them. So I think my next step is to recreate the geometry using the CAD features from CAESES. I did a "Split by Angle" on my imported geometry and appear to have my features of interest highlighted, see the attached screenshot. The highlighted red circles are not open edges, they are connected to other hidden geometry.

I would like to recreate that cylinder and then parameterize the smaller holes that are in it. The hidden geometry is very complex and I would like to not recreate that, and would prefer to only replace the shown tube (and the immediately related geometry required to make a closed manifold with the existing complex geometry). I see that I can create a circle from three points, so I tried to place 3D points on the red curve. This seems to result in an error of X, Y, and Z positions being NULL. Defining a point based on the centroid of the same edge does not give an error, but puts the centroid in the wrong location (appears to be at the global origin, one of my hidden geometries does have a curve centered at the global origin and is connected to what is shown, if that matters).

Am I not following the workflow correctly for replacing triangulated geometry with CAESES CAD geometry? I noticed I can create a BREP based on the shown geometry, but it fills in the smaller circles. However, the BREP does correctly place points on the selected edges. Is there a tutorial that talks directly about replacing triangulated geometry with CAESES CAD geometry? The mesh morphing tutorial doesn't really do what I want, and all searches for CAESES and STL files brings me back to that. I don't have access to this geometry in any other format than STL or CONVERGE surface (that is, no STEP or IGES).

Thank you for your assistance,
Joshua

[Mr. Heinrich von Zadow 9]

Hi Joshua,

if you want to change the positioning, number, shape and size of the holes shown in your screenshot I would indeed recommend, to re-model this part from scratch instead of morphing/deforming/shifting it...

I guess I'd start with a bare tube (i.e. a circle which you use in a BRep and extrude it) and then a parametric (in number, positioning, shape, size etc.) description for the holes (which I would create via a boolean operation). I just created a very simple example for you to explain the basic process, hope this helps to get you started.

Cheers,
Heinrich

demoTubeWithHoles.cdb

[viaexpress 0]

On 1/8/2024 at 3:55 PM, Mr. Heinrich von Zadow said:

Hi Joshua,

if you want to change the positioning, number, shape and size of the holes shown in your screenshot I would indeed recommend, to re-model this part from scratch instead of morphing/deforming/shifting it...

I guess I'd start with a bare tube (i.e. a circle which you use in a BRep and extrude it) and then a parametric (in number, positioning, shape, size etc.) description for the holes (which I would create via a boolean operation). I just created a very simple example for you to explain the basic process, hope this helps to get you started.

Cheers,
Heinrich

demoTubeWithHoles.cdb 452 kB · 0 downloads

How to upload image gif?

[Mr. Heinrich von Zadow 9]

You can simply drag&drop it from the file explorer.