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[ICEM] how can mesh this geometry ?

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Old   September 17, 2012, 11:34
Default how can mesh this geometry ?
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Hi all , sorry for this question , i am new in ICEM ...
how can mesh this geometry ?

triangular channel in rectangulat solid , water inside the triangular channel ...

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Old   September 17, 2012, 11:43
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Are both domains fluid? Ie the entire box minus the triangular prism is one domain and the triangular prism is a second domain?

The boxminus the triangular prism is the more interesting of the domains. There are two different topologies that spring to mind. The choice really comes down to your actual model; what surfaces are inlets/outlets/walls etc.? These will dictate the flow directions, then you can choose a mesh topology that aligns itself best with this.

The first potential topology is a simple 3D block split three times along the length, and the assosiate vertices to the corners of the triangle

The other potential topology is a C grid arond the triangular prism propogated out to the far walls. This will give you better alignment if the triangle is a source or a sink.


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Old   September 17, 2012, 12:11
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yes the entire box minus the triangular prism is one domain( solid ) and the triangular prism is a second domain( fluid)
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Old   September 17, 2012, 12:42
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thanks stuart23 for reply , can more explain ?
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Old   September 17, 2012, 15:03
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simple possible solution, four blocks

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Old   September 17, 2012, 21:04
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Quote:
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simple possible solution, four blocks

thanks Far.... I did this blocks but the mesh quality appeared poor , especially at the corner of triangular prism ...
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Old   September 17, 2012, 22:47
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that's why you need to add a Y-grid. it is the best suitable for those kinf of corners.
Take a look at the project i attached
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Old   September 17, 2012, 23:00
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Quote:
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that's why you need to add a Y-grid. it is the best suitable for those kinf of corners.
Take a look at the project i attached

thanks ali .... can explain to me how you take the block for tringular prism ?? i mean how to devide the geometry to 5 blocks ( one of them to triangular prism ) ......

thank you so much ..
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Old   September 17, 2012, 23:07
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take a look at this video:
http://www.youtube.com/watch?v=InyeCmEuUVM
y-grid is created, also some vertices are merged. everything you need is in this video.
time to go to sleep... see you tomorrow
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Old   September 17, 2012, 23:09
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Quote:
Originally Posted by diamondx View Post
take a look at this video:
http://www.youtube.com/watch?v=InyeCmEuUVM
y-grid is created, also some vertices are merged. everything you need is in this video.
time to go to sleep... see you tomorrow

thank you so much my bro ..... good night ...
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Old   September 18, 2012, 06:13
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slide the vertices of the middle downward to improve the quality. Or

1. Insert Y Block

2. Put O-grid
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Old   September 18, 2012, 06:19
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Quote:
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slide the vertices of the middle downward to improve the quality. Or

1. Insert Y Block

2. Put O-grid

thanks Far ..... i get confuse when i try to make Y-block
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Old   September 18, 2012, 11:39
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check this Quarter O-grid from vertices and !!!!!! Why?

and Video tutorials on some ICEM basic and sphere cube
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Old   September 18, 2012, 11:41
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thank you so much ...
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Old   September 18, 2012, 12:03
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Few snapshots for your case (you have fluid and solid regions ?)














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Old   September 18, 2012, 23:18
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Quote:
Originally Posted by Far View Post
Few snapshots for your case (you have fluid and solid regions ?)














yes i have fluid and solid regions ....

thanks bro
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Old   September 18, 2012, 23:24
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when i finish making mesh by ICEM with fluid and solid i read it by fluent , but in fluent only one zone appear ( solid ) why ???
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Old   September 19, 2012, 01:06
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Because you don't have the fluid region!!!

Right click on the parts then choose the last option (blocks). Rename to fluid and select the fluid blocks (blocks in Y-grid). Recreate premesh and convert to mesh. After that export the mesh and import into Fluent. You are done.
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Old   September 19, 2012, 01:17
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Quote:
Originally Posted by Far View Post
Because you don't have the fluid region!!!

Right click on the parts then choose the last option (blocks). Rename to fluid and select the fluid blocks (blocks in Y-grid). Recreate premesh and convert to mesh. After that export the mesh and import into Fluent. You are done.
really i thank you so much ..... i get it
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Old   September 19, 2012, 02:20
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Quote:
Originally Posted by malay View Post
I did this blocks but the mesh quality appeared poor , especially at the corner of triangular prism ...
When you have the triangular prisms, dont compare their quality to hexa. With prism, quality of 0.01 is also good enough

Here I am quoting one of the Simon's post regarding quality. Low quality Tet prism mesh post # 15

Quote:
If you haven't seen the inverted issue, then no worries... It happens only in 13.0 for redistribute prism, but is already fixed... In the mean time, the work around is to redistribute using the "Move => Redistribute Prisms" command. There isn't any more to tell.

Min tetra quality should probably be above 0.2, but if you have some below, it is probably fine, particularly in a non critical area. CFX is pretty robust, you could try as low as 0.05.

The Prism metric is really harsh in ICEM CFD. If you can get above 0.01, it will probably run fine in CFX... You could even go lower. (Maybe others can comment on their worst mesh that converged)...

Hexa, you are usually looking at min angle and aspect ratio... We shoot for an angle over 18, but will take anything over 9.
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