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mullzer February 22, 2012 14:50

Bocking Strategy Suggestions for 2d Trefoil Shape Inside Rectangle
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I am trying to model heat transfer for three individual cylinder in trefoil formation to their surroundings (see jpeg image CFD2). The trouble is that these meshes are not opening in Fluent (critical failure, error object #F).

I think the reason for this is that the mesh I have drawn in ICEM is inadequate as their is a blank space in between the three cylinders. No matter what way I split the main block I cannot got it it associate the edges to the entire perimeter of each circle which causes a problem for the computer. I was wondering if anyone had any suggestions on how I could split the blocks so that a mesh would go around each of the cylinders?

Currently, I have tried to make a block around each circle and delete the block that goes over the circle. I introduced a small gap between them to allow the mesh to continue into the centre (see jpeg image CFD). However all of my edges are horizontal or vertical and the mesh cannot continue join in from the two sides.

Any suggestions/ further questions are welcome.

Thanks in advance

mullzer February 22, 2012 19:09

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Due to the difficulties above, I am now trying to mesh the model as two separate models. I have meshed the inner part, and from what I can see there should be no problems with it (see image).

However, Fluent shows the error:
WARNING: no face with given nodes. Thread 9, cell 64
Clearing partially read grid.
Error: Build Grid: Aborted due to critical error.
Error Object: #f

Any ideas what is going wrong here?

mullzer March 2, 2012 15:06

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i am still working on this error. after reading a few other posts about similar problems, it seems that it is usually due to a the presence of a hole in the geometry. Mine is a straighforward flat model bounded by three walls so it certainly doesnt seem like it i put a hole in the geometry.

also when I run a gemetry check in ICEM it just says "done: 3 curves".

One interesting thing is that when I generate an automatic surface mesh it says there are hole in your geometry do you want to repair them.. and the it opens the geometry repair window but I am still unsure how to go about repairing it.

I managed to open the mesh in CFX without an error but the model is wrong (it is jagged all around the edges) so this must be where FLuent thinks there is a hole. I am wondering how best to fix this geometry in ICEM?

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