Meshing / gap refinement question

[Cnoj]

Hi,

When meshing the heat sink model below the depth of the refinement layers in the air gaps is varying across the model. As all my fin gaps are identical I was expecting the refinement layers in them to be identical. What's causing the variation?

Cad model:

I modeled each fin as three solids and each air path as a single solid.

Resulting mesh showing variation in refinement region thickness:

[johnsonshiue]

Hi! Is this Autodesk CFD? If not, I am not sure what we can do about it.

Many thanks!

[Cnoj]

Whoops wrong forum.

[Cnoj]

OK we're in the correct forum now.

Software is Simulation CFD 2105 v15.2

Thanks.

[LKania]

Refinement layer length scales are dependent (though not exclusively) on local mesh length scales in order to control element skewness within the refinement layers. Though the fin gap geometry is uniform across your model, the mesh length scales local to these fins are not, hence the refinement layers show some variation as well.

[Cnoj]

Which of the four fin gaps in my pic is closest to optimal? I'm using a fully developed velocity boundary condition to move the (fixed density) air and only interested in how well the fins conduct heat into the air.

Thanks,

Jon

[Jon.Wilde]

I would go with the left hand side, typically the more the better and you can test this by refining the mesh to see if the results change.

Check this out: Mesh Sensitivity Study.

Does that answer your question?

[Cnoj]

Do you mean more thicker or more in qty?  

[Jon.Wilde · Accepted solution]

More in quantity 🙂