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

Conjugate Heat transfer in CFX

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

Reply
 
LinkBack Thread Tools Display Modes
Old   December 7, 2010, 16:44
Default Conjugate Heat transfer in CFX
  #1
New Member
 
shyam
Join Date: Oct 2010
Posts: 17
Rep Power: 6
ksp1717 is on a distinguished road
Hi

I am trying to model a conjugate heat transfer problem in cfx. I went through the tutorial on CHT that came with the help files. It is on transfer of heat from solid coil to the flowing fluid. In my case, it is the reverse of that. A solid web is moving horizontally and hot air is coming in from the top and bottom of the web perpendicular to the web motion.

I modeled this similar to the procedure described in the tutorial. I create the solid domain inside the fluid domain used enclosure. generated the mesh. applied interfaces and boundary conditions. I ran the simulation and its running. But after my first run, I noticed that there is no heat transfer into the web.

Am I missing something here ? Do I need to change anything ?

P.S: I am new to CFD.

Thankyou

Shyam
ksp1717 is offline   Reply With Quote

Old   December 7, 2010, 17:06
Default
  #2
New Member
 
shyam
Join Date: Oct 2010
Posts: 17
Rep Power: 6
ksp1717 is on a distinguished road
Hi

I was going through some more threads here in the forum and found this. There one of the possible approaches mentioned was to get the heat transfer coeff from the cfd simulation and use it on the boundary of the solid and calculate the heat transfer in the solid.

Can this process be applied in my case. If yes can someone tell me how exactly i do it?
ksp1717 is offline   Reply With Quote

Old   December 8, 2010, 15:07
Default
  #3
Senior Member
 
Join Date: Mar 2009
Location: Europe
Posts: 168
Rep Power: 8
joey2007 is on a distinguished road
Is your case stationary or transient?
joey2007 is offline   Reply With Quote

Old   December 8, 2010, 22:06
Default
  #4
New Member
 
shyam
Join Date: Oct 2010
Posts: 17
Rep Power: 6
ksp1717 is on a distinguished road
I am not sure what you meant but im trying to simulate steady state with the solid domain moving at a constant velocity.
ksp1717 is offline   Reply With Quote

Old   December 8, 2010, 22:50
Default
  #5
New Member
 
Join Date: Dec 2010
Posts: 14
Rep Power: 6
kskong is on a distinguished road
Hi, I am new to CFD also, where can I find the tutorial files?

I need to model a CHT problem as well, internal flow through a certain solid structure which will generate heat. Any idea where to find relevant tutorial files?

Also, which is better to model CHT, CFX or Fluent? Thanks!!
kskong is offline   Reply With Quote

Old   December 9, 2010, 00:32
Default
  #6
New Member
 
shyam
Join Date: Oct 2010
Posts: 17
Rep Power: 6
ksp1717 is on a distinguished road
Hi

The tutorial files are located in the directory where you have installed openfoam. there is a directory named tutorials.

I dont have Fluent. But I tried my case in CFX. The simulaton setup was pretty straight forward. But it was not useful for my case since I dont know how to setup motion to the solid domain. But for you it should work just fine.

OF is simple to setup and all but the solvers available right now will do only the following
Compressible----transient and steady state
Incompressible--- transient.

Hope this helped you.

Shyam
ksp1717 is offline   Reply With Quote

Old   December 9, 2010, 01:58
Default
  #7
New Member
 
Join Date: Dec 2010
Posts: 14
Rep Power: 6
kskong is on a distinguished road
Hi Shyam,

I am running CFX in Ansys 12.1, I've found the tutorials.

By the way, what is OpenFoam??
kskong is offline   Reply With Quote

Old   December 9, 2010, 11:08
Default
  #8
New Member
 
shyam
Join Date: Oct 2010
Posts: 17
Rep Power: 6
ksp1717 is on a distinguished road
Hi

Sorry, I got confused a bit. I was trying to solve this problem both in CFX and OpenFoam (its an opensource CFD software).


Shyam
ksp1717 is offline   Reply With Quote

Old   December 9, 2010, 13:16
Default
  #9
New Member
 
Join Date: Dec 2010
Posts: 14
Rep Power: 6
kskong is on a distinguished road
I was learning CHT in CFX using the heating coil example from the tutorial. The tutorial uses calcium carbonate at the interface between solid and fluid. In my case, I do not have this "thin material", how should I define my interface ?
Thanks.
kskong is offline   Reply With Quote

Old   December 9, 2010, 15:27
Default
  #10
New Member
 
shyam
Join Date: Oct 2010
Posts: 17
Rep Power: 6
ksp1717 is on a distinguished road
I am not sure how that is done. I am waiting for some help myself.
ksp1717 is offline   Reply With Quote

Old   December 10, 2010, 17:35
Default
  #11
New Member
 
Join Date: Jun 2010
Posts: 20
Rep Power: 7
serezhkin is on a distinguished road
Did you try doing the opposite? Keeping the web steady and moving the fluid (i.e. switching to frame of reference of solid).
Also, you need to make sure you have enabled the thermal model (instead of isothermal) in solver setup.
If your interface is setup correctly (i.e. selected solid-fluid in interface properties, and specified a surface from solid and a surface from fluid), then you should have no problem getting heat transfer.
serezhkin is offline   Reply With Quote

Old   December 10, 2010, 23:07
Default
  #12
New Member
 
shyam
Join Date: Oct 2010
Posts: 17
Rep Power: 6
ksp1717 is on a distinguished road
Hi

I am successful in runing a simulation with a stationary web. Its similar to the case in the tutorial.
But my case involves both fluid and web moving.
Yes, I have enabled the Heat Transfer model to thermal energy for both web and the fluid.

Shyam
ksp1717 is offline   Reply With Quote

Reply

Tags
cfx, cht, heat transfer, multi domain

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
Conjugate heat transfer problem with porous media piko CD-adapco 1 April 17, 2009 15:41
CFX Heat Transfer RJamison CFX 0 July 24, 2008 12:11
Conjugate heat transfer for film-cooled flat plate Michele FLUENT 0 July 3, 2006 08:42
heat transfer in conjugate heat problems cirilo CD-adapco 1 April 18, 2006 09:16
Conjugate heat transfer (vs) periodic boundary mp FLUENT 1 January 13, 2003 02:38


All times are GMT -4. The time now is 23:57.