CHT-Problem: Gaps and intersections in CAD
 

Hi everybody, I'm quite new to STAR-CCM+. I now have a problem by working with geometry in ANSA which describes an assembly but there exist many intersections and gaps.

It is a CHT problem. I know it's okay by surface wrapper because only the largest internal Volume for the fluid domain is calculated. But the problem lies in the meshing in solid domain.

The intersections and gaps are mostly at the position where two pipes are connected. In reality one of the pipe is pressed into another. The distance between the gap, for example, is 0.45mm and the intersection is about the same depth. Now I'm wondering whether it is OK if I don't fix them in ANSA and directly import into STAR-CCM+. Details are drawn in the picture below. The first row displays the intersections/gaps. The second row are the possible solutions.

If I don't fix them, would it cause problems because of the intersection? Would the gap be transformed into an interface where radiation occurs?

If I have to fix them,what is the correct way to do so? Considering that the pipes are steel, should I combine the 2 parts into 1 in ANSA? Or should I duplicate the area where these two are in contact and define one to one part and another to another, so that the 2 pipes remain segregated? If so, how do I guarantee that the mesh of the 2 contacted area are conform?

Thanks a lot

Attachment 59140

Hi there
You could try the approach of shell meshing all components independently and then Release to FE-mod mesh and use Shell Mesh>Intersect [Solid Description]

Please refer to slide 29 of
http://www.beta-cae.com/pdf/ansa_met...esentation.pdf