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February 22, 2012, 12:43 |
ScalerField as a reaction rate
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#1 |
New Member
Mostafa Moghaddami
Join Date: Oct 2009
Posts: 13
Rep Power: 17 |
Dear All
I am going to use the incident radiation as a part of the chemical reaction rate. As I know the solvers such as reactingfoam get a constant rate not a scalerfield. I wonder if there is any way to introduce a scalerfield as a reaction rate in the chemical solvers. Thanks in advance for your help. Best Regards MM |
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April 6, 2012, 17:01 |
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#3 | |
New Member
Mostafa Moghaddami
Join Date: Oct 2009
Posts: 13
Rep Power: 17 |
Quote:
Dear Nima Thank you for your reply. Assume two species H2O2 and OH that dissolved in the water. Water is the inert component and does not appear in the reactions. There are two reactions: 1-H2O2->2OH rate=k1*G*[H2O2] 2-2OH->H2O2 rate=k2*[OH]*[OH] Assume that k1 and k2 are constant scalars and G is an available scalar field such as incident radiation. So we have: d[H2O2]/dt=k2*[OH]*[OH]-k1*G*[H2O2] d[OH]/dt=2*k1*G*[H2O2]-2*k2*[OH]*[OH] Thanks in advance P.S: In which university you are studying? |
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April 6, 2012, 17:42 |
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#4 | |
Senior Member
Nima Samkhaniani
Join Date: Sep 2009
Location: Tehran, Iran
Posts: 1,267
Blog Entries: 1
Rep Power: 25 |
Quote:
Code:
fvScalarMatrix firstEqn ( fvm::ddt(X) + fvm::div(phi,X) + fvm::Sp(2*k*Xw,Xw) == 2*k1*Y ); |
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April 8, 2012, 09:45 |
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#5 |
New Member
Mostafa Moghaddami
Join Date: Oct 2009
Posts: 13
Rep Power: 17 |
Dear Nima,
Thank you for your reply. I know that we can define any ODEs in OF and I did it already. The problem is that the set of transport equations of the species is stiff and does not converge. It seems that the OF solvers such as reactingFoam use some kind of limiters and adjust the time step in a way that the solution converges. I want to use the OF chemistry solvers that are used in reactingFoam. I want to modify the reactinFOAM solver and define an arbitrary scalar field for it. Do you know how I should do this? P.S.: I am studying in University of Tehran |
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April 8, 2012, 11:13 |
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#6 |
Senior Member
Nima Samkhaniani
Join Date: Sep 2009
Location: Tehran, Iran
Posts: 1,267
Blog Entries: 1
Rep Power: 25 |
sorry Dear Mostafa
i did not work with reactingFoam, so i can't be helpful here, you need to dig the code to find where that variable is used and whether it possible to change it or not. How much are you familiar with OpenFOAM coding? |
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April 22, 2012, 11:57 |
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#7 |
New Member
Mostafa Moghaddami
Join Date: Oct 2009
Posts: 13
Rep Power: 17 |
I am quite familiar but there are a lot of things for learning. How about you? What’s your field?
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Tags |
radiation, reaction rate, variable |
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