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Julie Polyakh January 7, 2004 09:16

Button 'Generate Mesh' doesn't work

I've created a new block and tried to mesh it from the 'Mesh' tab of the 'Create block structured grids' panel. I've set the number of cells for two block edges and pressed the button 'Generate Mesh'. In the output window appeared the following message:

"Ececute blocks 95 to 95 by 1

Error - Your increments are not reasonable

Error meshing block 95 - Block not meshed

No blocks meshed"

What increments is it talking about and what could be so unreasonable about them?

Thanks in advance,


steve January 7, 2004 10:34

Re: Button 'Generate Mesh' doesn't work
In a block you have 3 directions. Lets say you put 10 cells in direction 1. Then you must increment the vertices in direction 2 by at least 11. If you specify/force the vertex increment to be less than 11, then they are not reasonable. If you did not specify the increments yourself, maybe you need to give the block the number of cells on 3 edges (ie all 3 directions).

Julie Polyakh January 7, 2004 11:07

Re: Button 'Generate Mesh' doesn't work
I'm sorry, can you explain that in some other way. I just don't get what do you mean.


steve January 7, 2004 19:15

Re: Button 'Generate Mesh' doesn't work
A block has 3 directions, I, J, K. You specify the number of cells in each direction - say 10 for I, 5 for J, 2 for K. That means you have 10 cells in the I direction and 11 vertices and so on for J (5 cells, 6 vertices) K (2 cells, 3 vertices). So if you started numbering from 1, the first I row of vertices would be 1-11, the next 12-22, then 23-33...

What the program is complaining about is that it thinks you are trying to force a numbering system that is impossible. If the first row of vertices is numbered 1-11, then the second row can't possibly start at 5. The increment MUST be 11 or greater (make 1 block, set the edges at 10,5,2 turn on vertex plotting and see how it numbers).

I just built one myself and it works exactly as described. What I don't know is how you have managed this, but it is likely that you have used the BLKFACTOR command incorrectly (or the gui has messed up). Type HELP BLKF for more information and look at any of the tutorials that use blocks. Look at your echo file to see what the GUI has used for the blkf command.

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