CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > Siemens > STAR-CCM+

How do you set up a porous region

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   June 22, 2010, 08:02
Default How do you set up a porous region
  #1
New Member
 
james charlton
Join Date: Aug 2009
Posts: 27
Rep Power: 17
charltonjames is on a distinguished road
Hi,

Im a little confused on how to correctly set up a porous region. I know how to create a porous region. But im confused on what interface i should use (porous baffle?), Also how do you calibrate the settings - i.e. to have a 50/50 and 70/30 porous region? Any advice would be appreciated.

regards

James
charltonjames is offline   Reply With Quote

Old   June 25, 2010, 03:11
Default
  #2
Senior Member
 
Join Date: Mar 2009
Posts: 260
Rep Power: 18
Maddin is on a distinguished road
Read the manual.
It's very simple! Maybe you have to read the expression more than one time but with a little excel sheet you can set the pressure drop you need.
Maddin is offline   Reply With Quote

Old   June 29, 2010, 11:17
Default
  #3
New Member
 
james charlton
Join Date: Aug 2009
Posts: 27
Rep Power: 17
charltonjames is on a distinguished road
Thanks Maddin, but by the manual, do you mean the help files?

I've looked there and no luck.

Any chance you could expand you answer
charltonjames is offline   Reply With Quote

Old   June 29, 2010, 11:20
Default
  #4
Senior Member
 
Join Date: Mar 2009
Posts: 260
Rep Power: 18
Maddin is on a distinguished road
No the help files are only a "little" manual.
You should have some pdf-files in your ccm directory.
2000 pages strong... there you find all you need!
Maddin is offline   Reply With Quote

Old   June 29, 2010, 11:27
Default
  #5
New Member
 
james charlton
Join Date: Aug 2009
Posts: 27
Rep Power: 17
charltonjames is on a distinguished road
ah...... i didnt know this existed. Thanks maddin.... this could answer several of my questions!!! (i hope)
charltonjames is offline   Reply With Quote

Old   July 5, 2010, 09:00
Default Re:Porous
  #6
New Member
 
Niaz Ali Ahmed
Join Date: Jun 2010
Posts: 14
Rep Power: 16
niazaliahmed is on a distinguished road
There is a tutorial called Porous Flow. Go to Help>Training Guide. You may use an In-Place interface too.
niazaliahmed is offline   Reply With Quote

Old   July 5, 2010, 09:19
Default
  #7
New Member
 
james charlton
Join Date: Aug 2009
Posts: 27
Rep Power: 17
charltonjames is on a distinguished road
Thanks Niazaliahmed - I am using In-place interfaces now. I have a volume mesh and porous region. I just dont know what to do then - i.e. in the physics values in the porous region. I see there is a porosity setting (constant) which as default is set at one. I've tried changing this value to numerous values between 0 - 1.0 but nothing seems to work.

- I have tried the tutorial

If i apply the same process - i.e. Axisymetric Tensor; and random Pi and Pv values i do get a result. But i cannot validate this process or values or the accuracy of the given results.

Any further suggestions would be gratefully appreciated.
charltonjames is offline   Reply With Quote

Old   July 5, 2010, 12:11
Default
  #8
Member
 
Vinicius Girardi
Join Date: Mar 2009
Location: Sao Paulo, Brazil
Posts: 80
Rep Power: 17
Vinicius is on a distinguished road
The value of porosity just have effect when you are running unsteady simulations, if you are running steady, just set the Porous Inertial Resistance and Viscous Resistance.
Vinicius is offline   Reply With Quote

Old   July 5, 2010, 12:15
Default
  #9
New Member
 
james charlton
Join Date: Aug 2009
Posts: 27
Rep Power: 17
charltonjames is on a distinguished road
@Vinicius - Thank you. Thats fine. So i guess the next question is which Tensor you use? Following this i need to establish accepted values for initial and viscous resistance for trees.
charltonjames is offline   Reply With Quote

Old   July 6, 2011, 18:39
Default
  #10
Member
 
Join Date: Apr 2011
Location: US
Posts: 43
Rep Power: 15
famerfamer is on a distinguished road
Hey James,

Given a geometry, how to create a porous region from it? Thank.
famerfamer is offline   Reply With Quote

Old   July 6, 2011, 18:44
Default
  #11
New Member
 
james charlton
Join Date: Aug 2009
Posts: 27
Rep Power: 17
charltonjames is on a distinguished road
Sorry, i dont understand you question.
charltonjames is offline   Reply With Quote

Old   July 7, 2011, 06:54
Default
  #12
New Member
 
Join Date: Mar 2011
Posts: 1
Rep Power: 0
Scibor79 is on a distinguished road
Quote:
Originally Posted by charltonjames View Post
@Vinicius - Thank you. Thats fine. So i guess the next question is which Tensor you use? Following this i need to establish accepted values for initial and viscous resistance for trees.
Hi James

You've to choose the tensor according the flow direction in the porous region and its geometric characteristic.
you have to know if the porous region is isotropic un-isotropic, axial-symmetric etc.
For Inertial and Viscous resistance values you must have a characteristic curve (velocity/DP or similar) of the considered material.
If you need further help please describe your problem in detailed way

by
Scibor79 is offline   Reply With Quote

Old   July 15, 2011, 15:15
Default
  #13
Member
 
Join Date: Apr 2011
Location: US
Posts: 43
Rep Power: 15
famerfamer is on a distinguished road
Quote:
Originally Posted by charltonjames View Post
Sorry, i dont understand you question.
I mean do you know how to create a porous region including boundary and interface? Currently I have three parts vertically connected to each other, say A, B and C. B is the porous region which is sandwiched by A&C.

I just have no idea how to set B as a porous region and what parameters I need although I've read through that porous region tutorial...

Any help would be appreciated.
famerfamer is offline   Reply With Quote

Old   August 13, 2011, 19:29
Default
  #14
Member
 
Join Date: Apr 2011
Location: US
Posts: 43
Rep Power: 15
famerfamer is on a distinguished road
Quote:
Originally Posted by Scibor79 View Post
Hi James

You've to choose the tensor according the flow direction in the porous region and its geometric characteristic.
you have to know if the porous region is isotropic un-isotropic, axial-symmetric etc.
For Inertial and Viscous resistance values you must have a characteristic curve (velocity/DP or similar) of the considered material.
If you need further help please describe your problem in detailed way

by
Can I calculate those two resistance values based on the equation the tutorial provides? Thanks.
famerfamer is offline   Reply With Quote

Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
[Commercial meshers] Using starToFoam clo OpenFOAM Meshing & Mesh Conversion 33 September 26, 2012 05:04
Porous region set braket FLUENT 4 November 18, 2010 03:09
How to set BC for flow through porous plate TypeSpeed FLUENT 0 January 21, 2010 10:14
turbulence model for porous region Nina CFX 1 June 11, 2008 14:05
How to set environment variables kanishka OpenFOAM Installation 1 September 4, 2005 11:15


All times are GMT -4. The time now is 01:18.