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

Air-Oil Heat Exchanger trouble

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   September 8, 2008, 09:37
Default Air-Oil Heat Exchanger trouble
  #1
Gabriele Ansaloni
Guest
 
Posts: n/a
Hi all! I'm trying to solve a problem in which a Heat Excanger (made of aluminium) cools hot Oil using fresh forced air.

I have noticed that if i set the fluid in the air side at "Air at 25 C", CFX-Pre automatically sets "Air at 25 C" also as the oil side fluid; and if I set "Oil" in the oil side, CFX sets "Oil" also in the air one.

It seems that CFX acept only ONE fluid in the same simulation. In my opinion it's impossible that CFX does'n allow to simulate a simply Heat Exchanger, so I thing I'm doing something wrong.

I have tryed also whid bifasic fluid and mixtures, but unsuccesfully.

Does anyone have a suggestion to solve my problem?

Thank you all in advance Gabriele Ansaloni
  Reply With Quote

Old   September 8, 2008, 13:36
Default Re: Air-Oil Heat Exchanger trouble
  #2
F S
Guest
 
Posts: n/a
Hi Gabriele

Yes you are doing something wrong. Go through some basic tutorials if you have access to them.

Good luck
  Reply With Quote

Old   September 8, 2008, 19:19
Default Re: Air-Oil Heat Exchanger trouble
  #3
Glenn Horrocks
Guest
 
Posts: n/a
Hi,

By default CFX only allows one fluid for a single phase simulation. To do what you are trying to do and stay as a single phase simulation you have to activate an expert parameter, I can't remember its name. You might be able to find it in the documentation or ask CFX support.

Glenn Horrocks
  Reply With Quote

Old   September 9, 2008, 02:56
Default Re: Air-Oil Heat Exchanger trouble
  #4
sumedh
Guest
 
Posts: n/a
Hi Gabriele

Yes,CFX allows only one fluid, by default, for single phase simulation. To change it, create an environment variable named CFX5_NO_CONSTANT_PHYSICS and set the variable value = T, and then restart the machine.

Sumedh

  Reply With Quote

Old   September 9, 2008, 04:42
Default Re: Air-Oil Heat Exchanger trouble
  #5
F S
Guest
 
Posts: n/a
Hi

Or you can go to EDIT,click on OPTIONS, then click on CFX Pre and unclick on Enable Beta features to disable it.

BOL
  Reply With Quote

Old   September 9, 2008, 06:15
Default Re: Air-Oil Heat Exchanger trouble
  #6
Gabriele Ansaloni
Guest
 
Posts: n/a
YOU ARE A GENIUS!

Thank you all!

Gabriele Ansaloni
  Reply With Quote

Old   September 9, 2008, 22:59
Default Re: Air-Oil Heat Exchanger trouble
  #7
HekLeR
Guest
 
Posts: n/a
This env. var is replaced by a GUI option in 11.0. No need to restart.
  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
UDF for Heat Exchanger model francois louw FLUENT 2 July 16, 2010 03:21
Constant velocity of the material Sas CFX 15 July 13, 2010 09:56
Which Setup for Counterflow Heat Exchanger OF_User FLUENT 0 October 30, 2009 03:45
heat exchanger in typical air-conditioning system! Yang Bin Main CFD Forum 0 May 11, 2005 09:16
heat exchanger in typical air-conditioning system! Yang Bin FLUENT 0 May 11, 2005 08:53


All times are GMT -4. The time now is 16:59.