CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > FLUENT

Fluid Porosity : Value ?

Register Blogs Members List Search Today's Posts Mark Forums Read

Reply
 
LinkBack Thread Tools Display Modes
Old   September 24, 2004, 03:54
Default Fluid Porosity : Value ?
  #1
guru
Guest
 
Posts: n/a
Hello

For the modelling of the Porous zone, what is the usal value taken for "Fluid Porosity" (not Viscous(1/alpha) or Inertial Resistnce(C2)) for the cases where porous zone is simulating the Combi-Cooler?

Thanks & regards, -guru.

  Reply With Quote

Old   September 24, 2004, 12:23
Default Re: Fluid Porosity : Value ?
  #2
Evan Rosenbaum
Guest
 
Posts: n/a
Porosity = Volume of Fluid Divided by Total Volume

A porosity of 1 is all fluid, no solid. A porosity of 0 is all solid, no fluid.
  Reply With Quote

Old   September 25, 2004, 01:24
Default Re: Fluid Porosity : Value ?
  #3
guru
Guest
 
Posts: n/a
Thanks Evan,

So in the porous zone, say if I have 20 % of solid structure, then should I have to give Porosity as 0.8?

anyway thanks for the info, regards, -guru.
  Reply With Quote

Old   October 13, 2004, 18:44
Default Re: Fluid Porosity : Value ?
  #4
Ralf Schmidt
Guest
 
Posts: n/a
Hi, if you want to simulate the flow inside the cooler, dont use porosity -> from the fluent online-user-manual:

"Note that the porosity will never impact the flow velocity in the medium, [...] No matter what value you set for porosity, FLUENT predicts that the flow velocity is the superficial velocity in the medium"

http://eng.snu.ac.kr/down/on-line-do...ug/node233.htm

But you can use porosity together with a particle diameter to calculate C1 and C2. For example with the Ergun Equation.

As for the particle diameter, I would use any kind of relevant dimension of the divices inside the cooler. Porosity is simle to calculate.

Ralf
  Reply With Quote

Old   October 14, 2004, 00:43
Default Re: Fluid Porosity : Value ?
  #5
guru
Guest
 
Posts: n/a
Tanks Ralf...

I am working on it..let me see which one best predicts best results..

thanks once again.. -guru.
  Reply With Quote

Old   April 10, 2014, 13:49
Default
  #6
New Member
 
rao
Join Date: Apr 2014
Posts: 1
Rep Power: 0
vishalrao77 is on a distinguished road
for porous zone ,how to define the porosity of solid in fluent?.....can anyone help?
vishalrao77 is offline   Reply With Quote

Old   August 18, 2014, 08:15
Default
  #7
New Member
 
Naveed Iqbal
Join Date: Oct 2009
Location: Germany
Posts: 19
Rep Power: 7
niqbal is on a distinguished road
Hi Vshalrao,

you can set the fluid porosity in the porous zone properties. That is basically 1-(porosity of solid).
So for solid porosity = 0.4, you need to set fluid porosity = 0.6.
Hope this is what you are looking for.
niqbal is offline   Reply With Quote

Reply

Thread Tools
Display Modes

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 On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Water subcooled boiling Attesz CFX 7 January 5, 2013 04:32
fluid structure interaction taru agrawal FLUENT 4 September 10, 2007 03:12
How to apply negtive pressure to outlet bioman66 CFX 5 June 3, 2006 01:40
My Revised "Time Vs Energy" Article For Review Abhi Main CFD Forum 2 July 9, 2002 09:08
Terrible Mistake In Fluid Dynamics History Abhi Main CFD Forum 12 July 8, 2002 09:11


All times are GMT -4. The time now is 19:12.