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Old   February 24, 2011, 07:08
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hey, i already try it, and i able to mesh the face, but while meshing volume, i get this
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Old   February 24, 2011, 07:12
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i manage to mesh the face, it is success. But it is different for the volume, i get this error
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Old   February 24, 2011, 10:53
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you are trying to mesh a complex volume in one shot (you'll never succeed in that way)
you need to split your volume into subvolumes.
And you gave an element size which is very small.
So split your volume and use size fonction for controling your mesh size
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Old   February 24, 2011, 12:01
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err, how bro? only 1 volume there
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Old   February 25, 2011, 02:25
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yes you only have one volume, that's why I adviced you to split it into several small volumes.
>>>Volume/Split
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Old   February 25, 2011, 06:07
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so now what the step i have to do?
1) i will spilt the volume. (By the way, how to spilt it? just simply spilt it or spilt it as small and as simple as possible?)
2)mesh those spilted volume 1 by 1.
3)merged them back.
is this the way?
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Old   February 25, 2011, 06:14
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1- split your volume where you think you need to refine your mesh, and where you think you can apply an hexa mesh (simple geometries like cube, cylinder etc...)
2- yes
3- no, don't merge back your volumes (gambit will glue them together)
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Old   February 25, 2011, 09:12
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meaning i dont have to do step 3? gambit automatically joint aka "glue" them back?
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Old   February 25, 2011, 09:19
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no you don't need step 3
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Old   February 25, 2011, 09:52
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and the size function is necessary>?
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Old   February 25, 2011, 09:54
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and another question, after i spilt the volume, let say not on the exactly on the boundary, eg like the PSU, in my case it is not purely cube, so i spilt a cube slightly larger then the PSU, is it ok?
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Old   February 25, 2011, 09:59
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This is my first volume spilted and mesh, is it ok?

i am using spacing of 2 in order to save time, is it necessary to change to 1?
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Old   February 25, 2011, 10:01
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you are free to split your domain as you want.
Regarding the size fonction, it is not necessary to use them, but it is very helpful for controling the mesh refinement
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Old   February 25, 2011, 10:05
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Where this size function be generally used?
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Old   February 25, 2011, 10:08
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grid refinement >> check help
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Old   February 25, 2011, 10:25
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I have an idea here, if i can redo all this again, mean before i unite all this volume and subtract to get the fluid domain, can i copy all this volume inividually once? like copy each of PSU, HDD and so on. then after i done all the procedure and want to spilt volume, i just move back the copied item to thier respective locaton, so that i can use spilt volume with volume easy, can i>?
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Old   February 25, 2011, 11:16
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you want to split your domain with HDD volume, etc...?
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Old   February 25, 2011, 11:30
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This is what i done, at the figure, volume 313 is the volume i subtract (the fluid domain). And u can see that volume 314 is the volume which exactly the same (i guess) for the fan heat sink, this (volume 314) volume is i copy the original volume and place at the same location on it before i perform the spilt. However, spilting is success, as shown in figure, but i still fail to mesh volume 314

By the way, in the volume spilt option there is biderectional, connected, and retain, what that 3 option for?

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Old   February 28, 2011, 03:15
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No the volumes are not the same. Only outer surfaces are the same.
From your flow domain you already substracted this fan. I can see it, because when you pick the whole flow domain, outer surfaces from this fan are highlighted, meaning that the surfaces are outer surfaces from fow domain.
Now splitting the fan volume from the flow domain should fail, since there is no fluid domain inside the fan (hollow).
End even if it worked, I don't understand what you wanted to do...
Once again I don't advice you to import fans.
If you really want to include fans, then create a cylinder which diameter is greater than fan's one, and split your domain with it.
The cylinder will surround your fan and you will be able to pick it for meshing (cylinder substracted with fan).
Then try to mesh it.
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Old   February 28, 2011, 08:55
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Oh, ok bro.. I will try that. Meanwhile, for your knowledge, beside the geometry which guided by u, i have do 1 alternative on my own, and it is the simplified version. And, i managed to mesh as shown in the figure below. However, when i import the case file to FLUENT, test.msh in this case, i got the following error. Why?
Building...
grid,
Note: Separating wall zone 3 into zones 3 and 1.
wall -> wall (3) and wall:001 (1)
Warning: ST_Malloc: out of memory.malloc_storage: unable to malloc cell1, size 51779932, t 15, myid 1000000.

Error:
FLUENT received fatal signal (ACCESS_VIOLATION)
1. Note exact events leading to error.
2. Save case/data under new name.
3. Exit program and restart to continue.
4. Report error to your distributor.
Error Object: ()
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