CFD Online Logo CFD Online URL
Home > Forums > CFX

How EDM model works in CFX-5?

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

LinkBack Thread Tools Display Modes
Old   June 18, 2002, 17:03
Default How EDM model works in CFX-5?
cfd guy
Posts: n/a
Hi everybody,
I want to make a simple test with the EDM combustion model in CFX-5. My reacting fluid is Hydrogen Air (H2, O2, N2 and H2O). I've defined N2 as the constraint equation. I have several inlets and I've set the following mass fractions: 0.21 for O2, H2 = H2O = 0. In just one inlet I've set 1. for H2 and 0. for the other species. I'm not using any radiation model.
First I've solved the turbulent flow and then I switched off the fluids and tke and epsilon equations. After a few iterations of the energy and mass fractions equations I've noted no presence of the H2O in my solution and no change in the temperature field, ie. no reaction. What did I forget to set? I tested both Bulk Viscosity and Kinematic Viscosity. My initial conditions for the flow are a cold flow converged solution and for the species are "Automatic with Value" : H2 = H2O = 0. ; O2 = 0.21
Thanks in advance, cfd guy
  Reply With Quote

Old   June 19, 2002, 17:33
Default Re: How EDM model works in CFX-5?
Posts: n/a
Make sure you have some initial products in the domain. So, try reinitialising the H2O mass fraction to a non-zero value, say 0.01 or something and rerun it.

Set the H2O mass fraction to "Value" in the CCL to do this, rather than "Automatic with Value".

  Reply With Quote

Old   June 20, 2002, 10:35
Default Re: How EDM model works in CFX-5?
cfd guy
Posts: n/a
Thanks Neale,
But I found that the simplest way is to start from the scratch solving all equations together and the combustion effects will appear naturally. However, someone told me that is possible to trick the code and start a combustion problem from a cold solution modifying a simple coefficient in the EDM model.
Regards, cfd guy
  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
about Subgrid-scale model impecca OpenFOAM Running, Solving & CFD 4 December 20, 2013 11:36
"Full" buoyancy model in CFX Jade M Main CFD Forum 2 March 18, 2010 13:08
Reynolds Stress model in CFX vs Fluent Tim CFX 1 October 7, 2009 06:19
where to set CFX Transition Model? steven CFX 6 January 17, 2007 12:19
Use of 1 equation turbulence model in CFX 4.3 Niels Deen CFX 0 July 19, 2000 08:50

All times are GMT -4. The time now is 07:14.