[Andrew Norfolk]

Hi everyone. I've been trying to mesh a heatsink for almost two weeks now, It feels like something new is always going wrong! It's a large 58 straight finned device with unsymmetrical heat loads so I have to mesh the whole thing.


Ultimately I am hoping to import the mesh into CFX in order to carry out a conjugate heat transfer analysis. My work flow has been as follows:

Import geometry (heatsink with surrounding fluid volume as a separate body and shared interface). This includes points, lines and surfaces from the simplified CAD model.

Create two material points, AIR and HEATSINK representing the fluid and solid regions respectively.

Initialise the blocking for FLUID and split the blocks to match the geometry. Add blocks correpsonding to heatsink to HEATSINK.

Associate all edges, points and surfaces to the imported geometry.

Set pre-mesh Parameters (edge bunching).

Generate Pre-Mesh (For some reason this only works properly if I set projection to no projection, project faces is causing strange element behaviour inside the thin fins)

Convert to unstructured mesh.



Now the problems begin. When I try to check my mesh I get errors corresponding to non-manifold vertices, single-edge elements and multiple edges.

When this mesh is imported into CFX it creates some odd looking primative 2D regions inside of the mesh itself.


Can anybody tell me where I am going wrong? I thought structured meshing was supposed to be simple, I've done every tutorial there is. This is all so unbelievably frustrating.

[Andrew Norfolk]

In case anyone stumbles on this from a Google search I'll explain how to fix this kind of problem. When you see these strange 2D elements forming it is possibly a sign that the mesh is trying to project a face where it shouldn't be.

For me I had accidentally projected some internal faces inside the fins to the surface on the outside of the fins. This was forcing the elements to bunch towards the outside of the fins and explains why the project faces option was not working for my pre-mesh. The problem was remedied when I removed the association from these internal faces.