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

sharp temperature decrease near the wall

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   January 28, 2009, 09:23
Default sharp temperature decrease near the wall
  #1
dace
Guest
 
Posts: n/a
I have read in the manual that adiabatic boundary condition in case radiation heat transfer is activated means that temperature is adapted to ensure the sum of all heat fluxes to be zero q_rad+q_cond=0. Does anyone could help me to understand wheather obtained result is physical: there is a steady combustion process (eddy dissipation and k-epsilon) - the hottest flame is in the center, temperature slowly lowers when approaching the wall and then a sharp (~70 K) decrease of the temperature occurs in the 1st wall element thickness. I tried a finer mesh and the same situation occurs - temperature sharply decreases in the one element thickness near the wall (element is ~0.5 mm thin and velocity below 1 m/s). In this situation as far as I understand q_rad and q_cond has got the same direction near the wall what is not in agreement with q_rad+q_cond=0, am I wrong? Balances and residuals are low enough for corvergence. In case radiation is not activated everything seems ok.

thank you in advance for any comment on this issue
  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] Fluent3DMeshToFoam simvun OpenFOAM Meshing & Mesh Conversion 50 January 19, 2020 16:33
Gradation of temperature in wall boundary panos_metal FLUENT 1 November 26, 2010 15:21
Wall temperature define in fluent zdz198728 Main CFD Forum 3 November 19, 2009 01:37
Errors running allwmake in OpenFOAM141dev with WM_COMPILE_OPTION%3ddebug unoder OpenFOAM Installation 11 January 30, 2008 21:30
Multicomponent fluid Andrea CFX 2 October 11, 2004 06:12


All times are GMT -4. The time now is 04:32.