steady-state combustion using density
 

I model the combustion of methane in the burner (reaction CH4 + 2O2 => CO2 + 2H2O). I am wondering whether there is any stationary solver for combustion in openfoam. In my case, take into account the density of gases.

Is there a steady-state version of rhoReactingFoam solver?

Hi,

As far as I know there is know steady state solver but you can try two things:

1) Try mentioning "steadystate" for ddt discretisation in fvSchemes file. This may have some stability issues while running.

or

2) You may edit the source code altogether and create a new solver of your own. Here you can take care of any problems that may come up.

I was myself thinking of makin a steady state solver. So if you try the latter then please tell what all steps did you take.

This is not a good idea. If one wants to have a steady solution using a transient solver, ddtschemes should be set to CoEuler or SLTS. These two use local time step limitation (Co based for CoEuler and diagonal dominance based for SLTS) in order to obtain a steady solution.

When I am trying to change this I get the following error (for steadyState, CoEuler and SLTS):

--> FOAM FATAL IO ERROR:
attempt to read beyond EOF

file: /home/......./simple_mixer_test_6_steady_CoEuler/system/fvSchemes::ddtSchemes::default at line 20.

From function ITstream::read(token&)
in file db/IOstreams/Tstreams/ITstream.C at line 83.

FOAM exiting

so it looks that it is not possible to change to steady state by changing fvSchemes

I already succeeded in getting the change to SLTS or coEuler ddtscheme to run, next challenge is to get convergence...

For other people trying the change the ddt scheme for combustion, these slides might be helpful.

Steady State
 

Dear All,

I'm doing also the same job with OpenFoam, but until now, i didn't get the semialer result as I got in Transient mode. I made several steady-State Solvers, but seems that No Combustion happens! I'm using the 'psi Combustion Model' which is used in reactingFoam Solver as well. If any of you could run the Transient Solver in Steady-State mode ( with delta T=1 for example , and not with deltaT= 10^-6) or already created a new steady-state solver , I would be so grateful if help me this way,

looking forward to your replies,

Sincerely,

Parsa :)

Hi Parsa,

It is worthwile looking at libopensmoke for a steady state combustion solver

Regards,

Dear TBO,

Thanx for your quick reply and your hints, i read that page already, but couldn't find my answer there, but i will ask it there as well :)


cheers :)

Update on the topic, in the new OF release LTSreactingFoam is available, which is steady state version of reactingFoam (didn't try it yet)

I think LTSreactingFoam is something like LTSinterFoam. For the LTSinterFoam, it can't obtain a reasonable solution as interFoam for what i tried before. Anyone has an idea about that?