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[ICEM] Edge Parameters Question

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Old   August 14, 2013, 04:34
Default Edge Parameters Question
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Hi,

I use ICEM 14.5 Hexa to mesh some geometry.
Now, one of the edges doesn't behave as I expect:
I use "Exponential2" mesh law, what I want is
  • Spacing 1 = 0.4
  • Spacing 2 = 0.005
What I get is:
  • Spacing 1 = 0.63
  • Spacing 2 = 0.005
I found out, that I need to increase the number of nodes to get what I want.

The question is: How can I let ICEM choose the ratios so I get the two mesh spacings?
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Old   August 14, 2013, 09:33
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I guess it also depends upon the initial size. Try playing with that.
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Old   August 14, 2013, 10:09
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if you have one edge of 1 mm, and decided to add two nodes in the middle with a uniform spacing of 0.1. you can't, it is impossible. you need to add more node, ie 10 nodes in total. you figured it out by yourself.
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Old   August 14, 2013, 10:12
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What I was wondering about:
When I start with 0.005 spacing, why can ICEM end with a certain value on the other side, but not with a smaller value? Should be pretty simple, when the initial growth rate is reduced...

Edit:
If I understand the ICEM help correctly, using "Exponential" I can only choose the first cell height and the number of nodes, everything else is calculated. Can anyone confirm that?
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Old   August 15, 2013, 10:11
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You could interactively and iteratively adjust your ratio 2 (with your number of nodes fixed) and see if it gives you the size you are looking for...

If you have enough nodes, it may work out.

At the moment, the ratio is growing too fast so Spacing 1 is getting too large. Reduce Ratio 2 and see what happens.
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Old   August 15, 2013, 10:13
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I should point out (in case it isn't obvious), that Exponential 2 does not take your spacing 1 setting into account. If you want it to, you can use one of the other options (such as bi exponential).

You could also choose the option "From Graphs" and switch the Graph function to "exponential" and control it that way.

Best regards,

Simo
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