CFD Online Logo CFD Online URL
Home > Forums > FLUENT

Conjugate heat transfer - Free convection

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

LinkBack Thread Tools Display Modes
Old   May 16, 2011, 11:23
Default Conjugate heat transfer - Free convection
Senior Member
Join Date: Mar 2009
Location: Indiana, US
Posts: 185
Rep Power: 8
delaneyluke is on a distinguished road
Hi Guys,
I know the title seems like something discussed a dozen times before but hear me out please.
I've got the wall of a cooler, so cold air inside and ambient outside. Wall consists of steel and insulation. A simple heat balance gives me the heat flux and convective htc's (inside and outside)
Now attempting a 2D comparison with fluent and am just not able to match the htc's calculated, not even close.
It's purely laminar with a rayleigh number in the power of 10^3 on both sides. So have been running a 2D laminar sim with fixed values of temp for the inside and outside fluid domains.
I've tried constant dens, bousinesq and ideal gas but to no avail. Temp diff between outside and inside is around 20 degC.
I've considered a BL mesh to capture the thermal BL at the surfaces, adjusted relaxation parameters but htc's just dont come close.

Any suggestion please.

delaneyluke is offline   Reply With Quote

Old   May 24, 2011, 23:14
New Member
Oky Andytya
Join Date: Nov 2010
Posts: 26
Rep Power: 7
oky is on a distinguished road
Hi everyone,

I need help, how to get the value of convection coefficient [h] from Fluent directly?
Thank you.

Best regrads,

oky is offline   Reply With Quote

Old   May 25, 2011, 05:08
Join Date: Apr 2009
Location: Munich, Germany
Posts: 30
Rep Power: 8
sandeep_tu is on a distinguished road

CHTC depends upon the reference temperature which u give in the REFERENCE VALUES panel. In natural convection consider the gravity and try with incompressible ideal gas(for density).

May be explain ur problem bit more detailed.


U can get the CHTC values directly from reports--surface integrals---area wtd avg---wall flux---surface heat transfer coeff

sandeep_tu is offline   Reply With Quote


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 taw CFX 4 May 4, 2011 20:14
Conjugate heat transfer and radiation modeling questions shankara.2 FLUENT 0 April 21, 2009 15:55
Unreal temperature in conjugate heat transfer CFD joe FLUENT 1 August 9, 2006 09:23
free surface heat transfer! NR FLUENT 5 May 6, 2004 05:35
conjugate heat transfer problem Andreas FLUENT 2 February 6, 2002 04:15

All times are GMT -4. The time now is 10:39.