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-   -   OnlineLibrary in chemistryModelC Tommaso development (http://www.cfd-online.com/Forums/openfoam-solving/59272-onlinelibrary-chemistrymodelc-tommaso-development.html)

zurdo August 7, 2007 09:19

Hi.. this message is particul
 
Hi..
this message is particularly for Tommasso, who I belive implemented the chemistryModel.C

Cold you give me a brief explanation about this onlinelibrary as I am having errors using the combustion model with chemkin files.

There is a complete set of info as: tolerance,logT,cleanAll, etc in the online distionary, which i dont know what they mean?

Some tips are welcome.

Thanks.

Sergio

lucchini August 7, 2007 14:58

Dear Sergio, onlineLibrary
 
Dear Sergio,

onlineLibrary is used to tabulate the complex chemistry to reduce the computational time. It is a constant approximation version of the ISAT (in-situ adaptive tabulation) algorithm developed by Pope.

If you want to use the tabulated chemistry, the onlineProperties dictionary should be written as follows:

onlineProperties
{
tauStar off;

online on;

tolerance 1.0e-5;

logT off;

maxElements 100000;

cleanAll off;

scaleFactor
{
otherSpecies 1.0;
Temperature 1700;
Pressure 1.0e+10;
}

scaleFactorSolution
{
otherSpecies 1.0;
Temperature 1700;
Pressure 1.0e+10;
}

}

if you want to switch it off,

onlineProperties
{
tauStar off;

online off;

tolerance 1.0e-5;

logT off;

maxElements 100000;

cleanAll off;

scaleFactor
{
otherSpecies 1.0;
Temperature 1700;
Pressure 1.0e+10;
}

scaleFactorSolution
{
otherSpecies 1.0;
Temperature 1700;
Pressure 1.0e+10;
}

}

In the ISAT algorithm chemical source terms are tabulated into a binary tree and are used to approximate the chemical source terms of the nearest composition according to a specified tolerance.

Explanation of the terms:

tauStar: switch it off, it will be used in the future;
logT: if this option is switched on, the logarithm of the temperature will be tabulated instead of the temperature
maxElements: maximum number of elements to be tabulated (up to 5e6 is fine, then you can seriously run into memory troubles)
cleanAll: if switched on, it will clean the library after any time step. If you want to exploit the full capabilities of the method, switch it off
scaleFactor: tabulated data consist of chemical compositions, temperature and pressure. You can scale chemical compositions, temperature and pressure to get more points found
solutionScaleFactor: the same but used to extend the validity range of a tabulated composition.

For further details, please refer to the Pope's paper (you can find them on the web also) and to the code implementation. In particular
- chemistrySolve.C
- chemistryOnlineLibrary.C
should be fine to start looking at them.

If you need more help or you like to setup a possible collaboration, please contact me.

That's all for the moment, have fun with OpenFOAM and combustion.

Tommaso

zurdo August 8, 2007 06:30

Dear Tommaso, Thanks for y
 
Dear Tommaso,

Thanks for your replay.
I am or I was working extensively in fire and combustion. Actually, I did not use much detailed chemistry but mostly Flame Surface Density approaches and Thickened Flame in LES.
I was in the seminar in Zagreb and I congratulate you for you work in internal comb engines.
This is my first time using PsR model for combustion and this shortcut called ISAT. I am printing out some papers and see if they are useful for me.

These are my lines of work:

1) I am particularly interested in autoignition. I believe that it is important for IC as well?.

I am using a 3 step reaction CH4-O2 mechanism. Originally developed for P up to 100 bar.

2) DDD(Detonation to Deflagration). We are not sure about the combustion model to choose. In Open FOAM we could find: the progress variable approach (FSD) using wrinkling factor and burning turbulent velocities and PsR (using ISAT). I dont see any other combustion model.
In this DDD project, I am doing some mesh refinement by scalar quantity. I made some progress but it takes time and I don't have it. So, far I managed to do the dynamic refinement but there is an error when when in the unrefinement. The idea is to follow the flame front at the shock and combustion wave. This is samething could be interesting for you as to refine where the flame front it is.

3) Fires, I need to implement a new combustion model for fire in Open FOAM and new radiation model.

Thanks for your time. and if it is possible to find some common ground I am happy to any collaboration. If you want what I have done so far for the refinement you can have a look. Just let me know.

Thank

Sergio Ferraris.

markusrehm December 19, 2007 12:19

Hello Tommaso, a few questi
 
Hello Tommaso,

a few questions regarding the ISAT-tabulation:

I put your suggestions in the chemistryProperties file in the aachenBomb case. It doesn't seem to work. Do I have to switch it on at another place? Is there any output about the tabulation? I use the 1.4.1-dev-version.

Does it run with other solvers like reactingFoam as well?

Is the table printed out to a file?

Regards Markus.

stephan December 19, 2007 19:40

hi, where did you find ISAT
 
hi,

where did you find ISAT in the sources - and in which version is it implemented.
i was looking through the sources but couldnt find anything.
thanx
stephan

lucchini December 20, 2007 04:21

Stefan, did you get the fil
 
Stefan,

did you get the files I sent you by e-mail?

stephan December 20, 2007 04:37

hi, actually not - would be
 
hi,

actually not - would be nice if you can try it again..
thanx
stephan
p.s. please dont forget the .net instead of .de at the end.

lucchini December 20, 2007 06:11

Marcus, please send me an e
 
Marcus,

please send me an e-mail with your correct address since nothing of them works.

Thanks a lot,

regards,

Tommaso

markusrehm December 20, 2007 08:38

Hello Tommaso, yes I was in
 
Hello Tommaso,

yes I was in Zagreb. And I got your files. Thank you very much. I thought I saw the files in the dev-Version on the svn-Server. I am already on holiday so i can`t give you more information if it works or not. But next year... ;)

Regards and a blessed Christmas time to all. Markus

arun April 13, 2009 04:49

Hello Tommaso,

I am currently simulating detailed chemical kinetics combustion of diesel spray using dieselEngineFoam. I am using OpenFOAM-1.5.x.

Where can I find the ISAT in the source file?
And how do I "implement/switch on" ISAT in my case setting?
Is ISAT is implemented in dieselEngineFOAM?

Thanks in advance

Arun

Edison_Ge July 27, 2009 20:59

Hello Tommaso and everyone,
I'm doing PDF combustion simulation and now I'm using a DVOD for my chemistry. I find your implementation of the ISAT very interesting and eager to try it. But my concern is like:
1) I'm working on a 4 processor personal workstation. Does this ISAT implementation support parallezation.
2) I found some paper discussing ISAT with reduced chemistry, but I'm working with GRI-3.0 for methane/air. How's the codes' performance?

Hope some familiar with this chemistryonlinelibrary could help me clear these doubts.

Alish1984 March 17, 2011 14:17

Can anyone help me about using chemistryonline class in OF 1.5-dev?

riseguess December 26, 2011 16:52

ISAT ALGORITHM implementation in diselEnginefoam
 
Quote:

Originally Posted by arun (Post 212681)
Hello Tommaso,

I am currently simulating detailed chemical kinetics combustion of diesel spray using dieselEngineFoam. I am using OpenFOAM-1.5.x.

Where can I find the ISAT in the source file?
And how do I "implement/switch on" ISAT in my case setting?
Is ISAT is implemented in dieselEngineFOAM?

Thanks in advance

Arun

Hi Arun
did you to find answer to your to query. Can you please guide me in this regard as I want to use ISAT algorithm in dieselEngineFoam.

Shahid

riseguess December 26, 2011 17:09

ISAT ALGORITHM IN DIESELeNGIENFOAM
 
Quote:

Originally Posted by markusrehm (Post 198844)
Hello Tommaso,

a few questions regarding the ISAT-tabulation:

I put your suggestions in the chemistryProperties file in the aachenBomb case. It doesn't seem to work. Do I have to switch it on at another place? Is there any output about the tabulation? I use the 1.4.1-dev-version.

Does it run with other solvers like reactingFoam as well?

Is the table printed out to a file?

Regards Markus.

Hi Markus
did you manage to run the ISAT algorithm with dieselEngineFoam successfully. Can you guide me in this reagrd
Shahid

riseguess December 26, 2011 17:15

Quote:

Originally Posted by lucchini (Post 198842)
Dear Sergio,

onlineLibrary is used to tabulate the complex chemistry to reduce the computational time. It is a constant approximation version of the ISAT (in-situ adaptive tabulation) algorithm developed by Pope.

If you want to use the tabulated chemistry, the onlineProperties dictionary should be written as follows:

onlineProperties
{
tauStar off;

online on;

tolerance 1.0e-5;

logT off;

maxElements 100000;

cleanAll off;

scaleFactor
{
otherSpecies 1.0;
Temperature 1700;
Pressure 1.0e+10;
}

scaleFactorSolution
{
otherSpecies 1.0;
Temperature 1700;
Pressure 1.0e+10;
}

}

if you want to switch it off,

onlineProperties
{
tauStar off;

online off;

tolerance 1.0e-5;

logT off;

maxElements 100000;

cleanAll off;

scaleFactor
{
otherSpecies 1.0;
Temperature 1700;
Pressure 1.0e+10;
}

scaleFactorSolution
{
otherSpecies 1.0;
Temperature 1700;
Pressure 1.0e+10;
}

}

In the ISAT algorithm chemical source terms are tabulated into a binary tree and are used to approximate the chemical source terms of the nearest composition according to a specified tolerance.

Explanation of the terms:

tauStar: switch it off, it will be used in the future;
logT: if this option is switched on, the logarithm of the temperature will be tabulated instead of the temperature
maxElements: maximum number of elements to be tabulated (up to 5e6 is fine, then you can seriously run into memory troubles)
cleanAll: if switched on, it will clean the library after any time step. If you want to exploit the full capabilities of the method, switch it off
scaleFactor: tabulated data consist of chemical compositions, temperature and pressure. You can scale chemical compositions, temperature and pressure to get more points found
solutionScaleFactor: the same but used to extend the validity range of a tabulated composition.

For further details, please refer to the Pope's paper (you can find them on the web also) and to the code implementation. In particular
- chemistrySolve.C
- chemistryOnlineLibrary.C
should be fine to start looking at them.

If you need more help or you like to setup a possible collaboration, please contact me.

That's all for the moment, have fun with OpenFOAM and combustion.

Tommaso

Hi Tommaso
Can you please guide me how can i use the ISAT algorithm with dieselEngineFoam successfully. I am new to openFoam world and would appreciate your guidance
Shahid


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