CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > OpenFOAM > OpenFOAM Post-Processing

Surface Heat Transfer Coefficient on a heated cylinder

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   March 21, 2022, 06:37
Default Surface Heat Transfer Coefficient on a heated cylinder
  #1
Member
 
Join Date: Dec 2021
Posts: 33
Rep Power: 2
Alczem is on a distinguished road
Hello everybody!

I am looking for answers regarding the heat transfer coefficient utility heatTransferCoeff in OpenFoam (v2106).


The case runs with chtMultiRegionSimpleFoam with radiation.
  • It is a hollow cylinder immersed in water, heated from the inside by a heating element (1000W) which radiates. The cylinder warms up and heats the external water surrounding it. The simulation runs fine.
  • I am looking to approximate the heat transfer coefficient between the cylinder and the water so I can get rid of the simulated water and shorten computation time.

Currently, I compute the HTC using the utility heatTransferCoeff and the mode Tref, and I compare it with the following formula in paraview:

htc = wallHeatFlux/(Twall - Tref)

with wallHeatFlux computed with the utility, Twall the local temperature and Tref = 333K (60C) the water temperature far from the cylinder.


The results between these two are similar, but they both give values betweend 5000 and 10000 W/m/K which seems huge for a htc in free convection, considering that the outer cylinder reaches a maximum temperature of 64C (4 degree difference with the reference temperature).

I ran the same simulation with Fluent. I get similar temperatures, but the "Surface Heat Transfer Coefficient" estimated by Fluent is around 70 W/m/K and the "Wall Adjacent Heat Transfer Coefficient" is similar to what OpenFoam gets, so 5000-10000 W/m/K.


So after all that:
  • What is the difference between the Surface Heat Transfer Coefficient of Fluent and the OpenFoam utility?
  • Does someone know how the Surface Heat Transfer Coefficient of Fluent is calculated? I could not find the answer online. Is it possible to obtain the same computation with OpenFoam?


Any hint is appreciated, and thanks to everybody who read the whole thing, I will provide any missing details!
Attached Images
File Type: png cylinder_cfd.png (21.2 KB, 4 views)
Alczem is offline   Reply With Quote

Reply

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
Surface Heat Transfer Coefficient CFD Post MJ1105 Visualization & Post-Processing 0 February 19, 2016 04:57
Natural heat transfer in He tank with a heated rod inside cltormar CFX 3 January 16, 2015 17:59
High values of heat transfer coefficient for laminar flow in pipe Allankey CFX 2 May 28, 2014 12:44
Constant velocity of the material Sas CFX 15 July 13, 2010 08:56
Two-Phase Buoyant Flow Issue Miguel Baritto CFX 4 August 31, 2006 12:02


All times are GMT -4. The time now is 23:52.