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

Heat transfer between solid rotating and stationary fluid domains

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   November 10, 2015, 03:31
Default Heat transfer between solid rotating and stationary fluid domains
  #1
New Member
 
Sandor Sandor
Join Date: Jan 2015
Posts: 3
Rep Power: 11
DCSERE is on a distinguished road
Hi,

I would like to calculate the heat transfer coefficient between a solid rotating (rod) and stationary fluid domain (air) in CFX. I defined 600°C to the center surfaces of the rod (see the attached figure) and I want to get the temperature and the heat transfer coefficient distribution of the entire rod. A 20km/h velocity also was defined at the inlet.
The results don’t seem to be realistic because the temperature distribution of the rod is far from the axisymmetric. The airflow around the rod is not axisymmetric of course because 20 km/h also was considered. Since the rod rotates I expected an axisymmetric temperature distribution on its surface.
I also completed an analysis where the rotation of the rod wasn’t considered only the 20km/h, I got almost the same results. So it seems to me that the rotating domains is not accurate enough for the cases when we would like to calculate the heat transfer between a rotating solid domain and a stationary fluid domain.
I used frozen method, because only this option is available for fluid-solid interface in a steady state analysis.
Does anybody have any experience with the same problem?
Thank You in advance!
Attached Images
File Type: jpg heat_transfer.jpg (43.8 KB, 53 views)
DCSERE is offline   Reply With Quote

Old   November 10, 2015, 20:52
Default
  #2
Super Moderator
 
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,844
Rep Power: 144
ghorrocks is just really niceghorrocks is just really niceghorrocks is just really niceghorrocks is just really nice
First of all, have you read the FAQ on accuracy? http://www.cfd-online.com/Wiki/Ansys..._inaccurate.3F

What version of CFX are you using? Note that rotating solid domains is only supported from V15 onwards I think.
ghorrocks is offline   Reply With Quote

Old   November 17, 2015, 04:43
Default
  #3
New Member
 
Sandor Sandor
Join Date: Jan 2015
Posts: 3
Rep Power: 11
DCSERE is on a distinguished road
Dear ghorrocks,

Thank you for your answer. I am using Ansys V15.
Finally I found the reason of the problem, which was the following:
-in the first case I defined the rod as a stationary solid domain, then I changed the domain to the rotating one and I also set the option of the frame change of the interface from none to frozen rotor. Unfortunately I got the same results, so the rotation of the rod wasn’t considered in spite of the frozen rotor and the rotation of the rod were activated.
Finally I deleted the interface between the rod and the air and I defined it again using frozen rotor. In this case it worked well.
The conclusion is the following: if you define an interface for the first time using option none then you change it to frozen rotor the solver will calculate with the option none (I don’t know why). So you have to delete the interface and define it again using frozen rotor immediately.
DCSERE is offline   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
Convective term in heat equation for rotating solids vabishek OpenFOAM Programming & Development 8 June 24, 2020 12:10
Can CFX do CHT simulations with a solid domain rotating in a stationary fluid domain? acro CFX 15 September 23, 2016 12:16
Wrong flow in ratating domain problem Sanyo CFX 17 August 15, 2015 07:20
An error has occurred in cfx5solve: volo87 CFX 5 June 14, 2013 18:44
rotating solid zone with heat transfer Sasha FLUENT 1 March 24, 2009 17:55


All times are GMT -4. The time now is 23:41.