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Traib November 13, 2012 16:26

Is it possible to modify Janaf Model in OpenFoam 2.1.1?
Hello there,

I am a new member and this is first post here so I am trying not to sound too stupid though I think my title itself betrays me.

I have been working on supersonic combustion simulation and I think it has become quite obvious that I am destined to face the Janaf problem. I give some details below:
The simulation is related to high-Mach number reacting flows so I am trying to use rhoReactingFoam since this seems like the best choice to me. Normally the temperature should reach around 3-4000K but there are some jumps before convergence and once the Janaf problem appears its hopeless. I have worked at lower Mach numbers in fluent and had not many problems but it fails at higher Machs.
I have read several threads related to this problem here and I found this interesting thread by iyer.arvind ( about this new Janaf model that uses 9 coefficients.
The thread by Karam ( is very dicouraging but I think there are ways to modify the codes to suit my problem.
Now the iyer.arvind's thread is old and the patch he provides is for older OF. So I tried to modify the janafThermo files but now I am confused. Is it even right to work that way? Is it possible to simply modify the source codes using newer models? I thought I should ask for suggestion before I start putting my efforts into it because earlier efforts by others appear very discouraging.

Please reply if you have ideas about this.

wyldckat December 26, 2012 18:10

Greetings Traib,

Sorry for the late reply. I have no clue if you've found an answer to your question, but you might find some answers on this thread:

Best regards,

PS: As for Ehsan's questions, I've moved them to another thread, namely this one:

Traib December 28, 2012 06:35

Hi Bruno,

I had some help from your earlier posts in this thread about compiling user libraries:

I have since compiled solvers and thermo libraries but janafThermo is still a unresolved issue for me that I am currently working on. Using new 9-coeffs janafTable does not really solve the problem. For cases of high speed combustion, I am doing validation tests for a new solver based on experimental results and the old janafThermo data currently works on several cases but not without problems. One strange problem I am facing is that a case which runs well in serial computation stops in parallel computation using mpirun. This error still seems to be related to janafThermo calculations. Tmin drops way below 200 K as the flow from the subdomain containing the inlet passes into the following subdomain, and thats when the solution stops, without providing any reason for error.

I will go on to try checking if the problems discussed in the thread you have shared above affect my cases as well and see what I can get. Thanks for the reply.


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