[sidhant]

Hello Everyone,

I have a volume of air consisting mainly of three parts (entry, fins and exit) inside a heat exchanger (WCAC) which I have extracted from GT-Suite, as shown in the figure below.

geo.PNG
geo1.jpg
geo2.jpg
geo3.PNG

I have repaired the pierced faces, free edges and then imprinted each fin on upper (entry) and lower (exit) parts which created interfaces between them. However, when I try to do the volume mesh, I get the following error.

error_volume-mesh_edge-recovery.jpg

When I tried to locate the point where error occurred, It was found to be at the walls of the fin and it changes each time I try to mesh the volume.

I hope you guys can help me. I can review each step in detail if needed. I don't know what information to provide, so please don't hesitate to ask for any detail.

Thankyou in advance.

Sid007

[me3840]

Are you trying to do a conformal mesh between several parts? This will be difficult for this geometry unless you refine it quite a bit.

Have you tried meshing it with just the polymesher alone?

[sidhant]

Thankyou for the reply.

Yes I have been trying to do a conformal mesh. I used Polyhedral Mesher and it gave me the same error and meshing operation stopped.

Then I used thin Mesher for the fins, it gave me same errors but volume mesh got successfully completed (Although I could not understand how the meshing did not stop like before).

One more thing I need to show you is that when I select the interface (of one fin here) it displays the one highlighted in the figure below.

mesh1.PNG
mesh2.PNG

I thought it to be bad imprinting but when I checked the imprint it was fine(in figure below). Could you tell me why is it so?

mesh3.jpg

Sid

[me3840]

Check your surface mesh at that location, it looks like the problem is there. If you do not have a good surface mesh there's no point in volume meshing. It looks like that interface is not conformal at all.

Are you meshing just the solids? I find it is best for cases like this to mesh only the solids first and only with the polymesher to ensure that your imprints are all OK.

[sidhant]

Hello,

I am not sure if I properly understand the term meshing of solids. Did you mean mesh the three parts one at a time, then combine them and finally imprint them? Could you please elaborate your idea?

Sidhant

[me3840]

This is a CHT case, right? When I mean solids, I mean parts that are physically solids as opposed to parts that represent fluids.

[sidhant]

I think I understand now what you meant by solids. The model shown in the figures is an extracted volume (fluid). Yes, it is a CHT case.

[me3840]

Are there multiple solids or just one?

The first step to complex CHT cases like this is to completely forget about the fluid and mesh the solids only first. If you can't do that there's no point in doing the fluids.