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

Porous-Fluid Interface Treatment

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   October 2, 2019, 14:57
Question Porous-Fluid Interface Treatment
  #1
New Member
 
Farhad.a
Join Date: Oct 2017
Posts: 4
Rep Power: 9
farhad.a is on a distinguished road
Hello,

I have simulated a 3D air channel partially filled with porous media and examined the pressure drop and heat transfer in this channel. For the porous zone Forchheimer extended Darcy’s equation and the thermal equilibrium model have been employed and the flow has been considered as laminar flow, but for the fluid cell zone the flow is turbulent and RNG k-Epsilon turbulence modeling has been utilized.
The question is how two sets of governing equations are solved and how the interface between the domains (where each of these governing equation is applicable) is handled?

I mean i know there are different interface conditions such as The Ene, Levy and Sanchez-Palencia interface, The Beavers-Joseph interface, but i want to know which interface conditions does ANSYS Fluent use if i haven't selected one.
farhad.a is offline   Reply With Quote

Old   October 2, 2019, 15:36
Default
  #2
Senior Member
 
Lucky
Join Date: Apr 2011
Location: Orlando, FL USA
Posts: 5,760
Rep Power: 66
LuckyTran has a spectacular aura aboutLuckyTran has a spectacular aura aboutLuckyTran has a spectacular aura about
I don't think there is any special interface treatment.

When you select the laminar zone option, Fluent sets the turbulent production in that zone to zero. The variables (k, epsilon, etc.) are still transported through the laminar zone.

There is another option (accessed using TUI commands) that allows you to also set the turbulent viscosity to zero in the laminar zone. But again, they are simply transported.
LuckyTran is offline   Reply With Quote

Old   October 3, 2019, 02:26
Unhappy Porous interface
  #3
New Member
 
Farhad.a
Join Date: Oct 2017
Posts: 4
Rep Power: 9
farhad.a is on a distinguished road
Thanks for your reply.
But, there are extra terms in the momentum equation for the porous zone, the governing equations are completely different. I found just Porous jump treatment which is for 2D simulations and not the case for the 3D simulation that i've done.
I don't usually care about these equations, but the reviewer of the article that i've submitted has asked this question, and i have to answer it to submit the revised manuscript: "how two sets of governing equations are solved and how the interface between the domains (where each of these governing equation is applicable) is handled?"
farhad.a is offline   Reply With Quote

Old   October 3, 2019, 02:27
Default
  #4
New Member
 
Farhad.a
Join Date: Oct 2017
Posts: 4
Rep Power: 9
farhad.a is on a distinguished road
Thanks for your reply.
But, there are extra terms in the momentum equation for the porous zone, the governing equations are completely different. I found just Porous jump treatment which is for 2D simulations and not the case for the 3D simulation that i've done.
I don't usually care about these equations, but the reviewer of the article that i've submitted has asked this question, and i have to answer it to submit the revised manuscript: "how two sets of governing equations are solved and how the interface between the domains (where each of these governing equation is applicable) is handled?"
farhad.a is offline   Reply With Quote

Old   October 3, 2019, 03:52
Default
  #5
Senior Member
 
Lucky
Join Date: Apr 2011
Location: Orlando, FL USA
Posts: 5,760
Rep Power: 66
LuckyTran has a spectacular aura aboutLuckyTran has a spectacular aura aboutLuckyTran has a spectacular aura about
The pressure drop due to the porous media is handled by adding an extra volumetric momentum sink. If you need a reference, refer to the user manual section on Porous Media Conditions (see 7.2.1-3).

There is only one momentum equation. Refer to my previous post for why there is only one momentum equation when you use a laminar zone option. Interface treatment is needed in general when you actually have two separate sets of governing equations. But that is not the case.

Last edited by LuckyTran; October 3, 2019 at 12:14.
LuckyTran is offline   Reply With Quote

Old   October 3, 2019, 07:20
Default
  #6
New Member
 
Farhad.a
Join Date: Oct 2017
Posts: 4
Rep Power: 9
farhad.a is on a distinguished road
Again, Thanks for your reply.
farhad.a is offline   Reply With Quote

Reply

Tags
porous baffle interface, porous boundary, porous cell zone, porous domain, porous formulation

Thread Tools Search this Thread
Search this Thread:

Advanced Search
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 Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Fluid Domain moving with Rigid body Lloyd Sullivan CFX 3 August 17, 2018 10:58
fluid porous interface NewGuy CFX 8 February 21, 2017 00:04
Error - Solar absorber - Solar Thermal Radiation MichaelK CFX 12 September 1, 2016 06:15
Velocity vector in impeller passage ngoc_tran_bao CFX 24 May 3, 2016 22:16
Question about heat transfer coefficient setting for CFX Anna Tian CFX 1 June 16, 2013 07:28


All times are GMT -4. The time now is 11:29.