CFD Online Logo CFD Online URL
Home > Forums > CFX

Solver problem with a big amount of reactions

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

LinkBack Thread Tools Display Modes
Old   April 6, 2007, 09:30
Default Solver problem with a big amount of reactions
Posts: n/a
My reacting mixture include more than 100 chemical reactions, but as I noticed Solver doesn't run when I add more than 72 reactions. Here is error message I get -


ERROR #001100279 has occurred in subroutine ErrAction. | | Message: | | Stopped in routine MEMERR | ----------+

Is there any way to add more reations?

  Reply With Quote

Old   April 6, 2007, 12:51
Default Re: Solver problem with a big amount of reactions
Posts: n/a
Dear Leonid,

What version of ANSYS CFX are you using? 5.7.1, 10.0 or 11.0?

Please report the issue with your help representative.

There are no hard limit on the number of reactions allowed; therefore, something must have gone wrong..


  Reply With Quote

Old   April 9, 2007, 10:38
Default Re: Solver problem with a big amount of reactions
Posts: n/a

how many reactions has the solver actually been tested on? I remember some time ago there were some limits!


are you actually serious about applying such detailed finite rate chemistry in CFX? You realize that solving transport equations for each species is not only going to be very computationally expensive (I don't know how much because you do not specify how many species are involved in the 72-100 reactions) BUT guess that it is 30+???

Not only does your computation effor increase because of the additional transport equations BUT as you move from a model with major species and reduced reactions TO a model with minor species and elementary reactions -> you drastically expand the time (and spacial...people often forget about this!!!) scales that need to be resolved! This means you probably cannot run with as big of time steps either! And it may not even run on the same mesh as a global reaction model!

Ok then the big this a turbulent system. The detailed reaction mechanisms are only valid for homogenous systems so the mean sources (for species equations and energy) are not the same as the source evaluated at the mean values! All RANS will give you is the mean state values!

So all this effort may not give you anything useful anyhow?

Have you considered using a pdf based method? Do you have access in Ansys now to generate tables? Can CFX read PrePdf formats?

Things to think about....Bak_Flow

  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
thobois class engineTopoChangerMesh error Peter_600 OpenFOAM 4 August 2, 2014 09:52
Solver problem in Oscillating Plate tutorial vovogoal CFX 1 November 22, 2011 10:54
Problem with Solver when using Star CCM+ tutuabc STAR-CCM+ 0 April 15, 2010 10:23
problem about direct solver for sparse matrix ztdep Main CFD Forum 0 August 11, 2006 12:16
Can I use coupled solver for this problem Frank FLUENT 0 April 11, 2006 06:28

All times are GMT -4. The time now is 12:44.