HOW COULD BE A MIXTURE IN reac
 

HOW COULD BE A MIXTURE IN reactingFoam IGNITED?

Hello Mojtaba, set an initi
 

Hello Mojtaba,

set an initial temperature and a composition which will ignite. E.g. start the calculation without reaction and use setField to set the temperature at a ignition point to say 1500K.

Regards markus

hi thank you for advice
 

hi

thank you for advice

but with an initial high temperature the domain will be purged after some time steps.

this is not the way

I want a better method(to ignite)

ANY SUGGESTIONS PLS.!

IS NOT HERE ANY ONE TO SHARE E
 

IS NOT HERE ANY ONE TO SHARE EXPERIENCE ON THIS!!?

I think you have to look into
 

I think you have to look into diesel foam for this. Mixture is ignited over there. You can view its tutorial file to get an idea about ignition and stuff.

this is not the way you mentio
 

this is not the way you mentioned Arun.
ANY SUGGESTIONS???

Yes, I have a suggestion. stop
 

Yes, I have a suggestion. stop using caps!!!

After that you can go here and have a look.

http://openfoamwiki.net/index.php/Contrib_reactingFoam

N

thanks alot Nordin, it seems t
 

thanks alot Nordin, it seems to be useful.
but if a better trick could be applied instead of increasing enthalpy I think it would be better,because in some circumstances temperature rises above of therm.dat limits (3500) and we have a janaf thermo error

fixed! http://openfoamwiki.
 

fixed!

http://openfoamwiki.net/index.php/Contrib_reactingFoam

thank you! But this does no
 

thank you!

But this does not solve the problem NIKLAS!

Janaf thermo error still remains after enthalpy increase

Niklas you must first compu
 

Niklas

you must first compute temprature after:
h[ignCell] += ignSite.strength()*magH;

then evaluate enthalpy increase(enthalpy icrease must not cause T>3500),and after that apply:

h[ignCell] += ignSite.strength()*magH;

Another vague problem: Duri
 

Another vague problem:

During parallel run the term "ignSites.cells()" in file "ignite.H" returns no cell and ignition does not occur.

but with a single cpu there is no problem.

Any suggestions!!!

Another vague problem: Duri
 

Another vague problem:

During parallel run the term "ignSites.cells()" in file "ignite.H" returns no cell and ignition does not occur.
it does not depend on the number of cpus or the method of decomposition.
but with a single cpu there is no problem.

Any suggestions!!!

I thinks the problem arises wh
 

I thinks the problem arises when this function

"meshSearch::findCell" is called.

Is my guess true?

Any suggestion is appreciated!

Any help?
 

Any help?

Isn't here Some one to help wi
 

Isn't here Some one to help with this!

i am new to openfoam i am solv
 

i am new to openfoam i am solving one combustion problem, i need to run a combustion problem.... i used XI-foam as solver, while running some errors are coming... i need to know which solver is good for combustion problem.. and few guidelines for solving combustion problem.

i am new to openfoam i am solv
 

i am new to openfoam i am solving one combustion problem, i need to run a combustion problem.... i used XI-foam as solver, while running some errors are coming... i need to know which solver is good for combustion problem.. and few guidelines for solving combustion problem.

reactingFoam,dieselFoam and di
 

reactingFoam,dieselFoam and dieselEngineFoam solve non-premixed combustion.
Others solve premixed and partially premixed combustion

hi to everyone i am new to
 

hi to everyone
i am new to openfoam, i am using openfoam1.4, i want to solve simple methane combustion problem so which solver can i use for solving in openfoam.. already i solved in fluent... plz reply me

if Non-premixed -> reactingFoa
 

if Non-premixed -> reactingFoam
if premixed or partially premixed ->Xifoam

hello Mojtaba Shahmohammadian
 

hello
Mojtaba Shahmohammadian sir
i am solving this problem in XIfoam only.
my verticies are
convertToMeters 1;

vertices
(
(0 0 0)
(0 0.5 0)
(14 0 0)
(14 0.5 0)
(180 0 0)
(180 0.5 0)
(0 22.5 0)
(180 22.5 0)
(0 0 1)
(0 0.5 1)
(14 0 1)
(14 0.5 1)
(180 0 1)
(180 0.5 1)
(0 22.5 1)
(180 22.5 1)
);

blocks
(
hex (0 2 3 1 8 10 11 9) (14 1 1) simpleGrading (1 1 1)
hex (2 4 5 3 10 12 13 11) (166 1 1) simpleGrading (1 1 1)
hex (1 5 7 6 9 13 15 14) (180 22 1) simpleGrading (1 1 1)
);

edges
(
);

patches
(
patch inlet1
(
(1 9 14 6)
)
patch inlet2
(
(0 8 9 1)
)
patch outlet
(
(5 13 15 7)
)
wall topwall
(
(6 14 15 7)
(1 9 11 3)
)
wall bottomwall
(
(0 8 10 2)
(2 10 12 4)
)
empty frontandback
(
(8 9 11 10)
(0 1 3 2)
(9 14 15 13)
(1 6 7 5)
(10 11 13 12)
(2 3 5 4)
)
);

mergePatchPairs
(
);


// ************************************************** *********************** //
i need to define species seperately for air and fuel inlets, where i have to define species sir..

have a look at run/tutorials/d
 

have a look at run/tutorials/dieselFoam/aachenBomb
and you see how to define boundary

hi everyone i am solving one
 

hi everyone
i am solving one methane combustion problem, i am facing difficulty please any one can send one combustion solved problem through link for reference..

why reaction rate is zero?
 

Dear members,

I have a difficulty with reactingFoam.
When I calculate reactingFoam tutorial or dieselenginfoam tutorial, the reaction rate is always Zero. I have switched on the chemistry and combustion as well as using a high temperature ignition region, however, regardless of the temperature and Arrhenius parameters that I used in chem.inp, the reaction rate is always zero. I should mentioned that other transport properties and equation for species (YEq) is properly solved. The problem is just in the calculation of reaction rate.

Any help!

Hi,

where is the reaction rate calculated in dieselFoam?

Christof

the reaction rate is calculated in ~/OpenFOAM/OpenFOAM-1.5/src/thermophysicalModels/chemistryModel/chemistryModel

Mehdi,

how could you get access to the reaction rate?

Christof

hello niklas,
can you tell me how to compile the modified reactingFoam solver with wmake?
i typed "wmake" in the terminal and got this:

/applications/solvers/combustion/reactingFoam> wmake
linuxGccDPOpt/options:7: *** missing separator. Schluss.
wmake error: file 'Make/linuxGccDPOpt/objectFiles' could not be created

Access to specieThermo data
 

Dear All,

Does any of you know to access to the thermodynamic propertie of species such as hi(T) where hi is enthalpy of ith specie and Ti is temprature of cell?
In openFoam-1.5 you can write

hi = chemistry.specieThermo()[i].h(Ti); and it works. See disealengienfoam solver in openfoam-1.5.

However, in OpenFoam-1.6 if you write the same you get psichemistrymodel has no memebr specieThermo.

How can we use specieThermo in OpenFoam-1.6?
http://www.cfd-online.com/Forums/ima...ser_online.gif http://www.cfd-online.com/Forums/ima...reputation.gif http://www.cfd-online.com/Forums/ima...ons/report.gif http://www.cfd-online.com/Forums/ima...c/progress.gif http://www.cfd-online.com/Forums/ima...ttons/edit.gif

Its related to how the thermo is now a member of the chemistry (or vice-versa, it's been a while since I took OO programming). I am trying to figure it out to solve the problem stated in a thread I started recently.