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-   -   Reactions with porous medium (https://www.cfd-online.com/Forums/fluent/177843-reactions-porous-medium.html)

Yuting September 22, 2016 08:27

Reactions with porous medium
 
Hi friends

Could Fluent implement the porous medium reacting with gas flow? I'd like to simulate the coal particle react with hot gas and assume the fixed bed of coal as porous medium, the hot gas will penetrate the coal bed and react with coal particle. Any body can give me some advices? Really thanks for the help..Please

souza.emer July 15, 2019 14:06

I would like to know this too =/

Yuting July 15, 2019 22:12

Quote:

Originally Posted by souza.emer (Post 739017)
I would like to know this too =/

Hi, for the reactions involved in the porous medium, the possible solution is to write the UDF and UDS to describe the happened heat and mass transfer. Fluent itself seems does not provide the model access on the GUI. Hope this might help you.

Weiqiang Liu July 21, 2019 10:45

Quote:

Originally Posted by Yuting (Post 739051)
Hi, for the reactions involved in the porous medium, the possible solution is to write the UDF and UDS to describe the happened heat and mass transfer. Fluent itself seems does not provide the model access on the GUI. Hope this might help you.

I almost finished this project. However, the velocity contour is not very reasonable. Have you met same problem?

Yuting July 22, 2019 01:08

Quote:

Originally Posted by Weiqiang Liu (Post 739547)
I almost finished this project. However, the velocity contour is not very reasonable. Have you met same problem?

Hi,
I think there are many possible problems may cause the velocity contours unreasonable. For example, the incorrect boundary conditions including the porous medium properties, and the operational pressure, even the momentum source along with the mass source added into the porous zone. Maybe you can go back to check if these are correct and then modify your case. Hope this can help you.


Yuting

Weiqiang Liu July 22, 2019 11:15

Quote:

Originally Posted by Yuting (Post 739584)
Hi,
I think there are many possible problems may cause the velocity contours unreasonable. For example, the incorrect boundary conditions including the porous medium properties, and the operational pressure, even the momentum source along with the mass source added into the porous zone. Maybe you can go back to check if these are correct and then modify your case. Hope this can help you.


Yuting

actually, I am modeling diesel particulate filter. I've checked boundary conditions, porous media properties or operational pressure. The soot consuming rate and temperature magnitude are consistent with literature. However, I can never get that obvious filtration velocity like the author did.

I spend a lot of effort on this problem. You just told me mass source term may take an effect? Will mass source term influence velocity field?
Best regards.

Yuting July 23, 2019 19:56

Quote:

Originally Posted by Weiqiang Liu (Post 739672)
actually, I am modeling diesel particulate filter. I've checked boundary conditions, porous media properties or operational pressure. The soot consuming rate and temperature magnitude are consistent with literature. However, I can never get that obvious filtration velocity like the author did.

I spend a lot of effort on this problem. You just told me mass source term may take an effect? Will mass source term influence velocity field?
Best regards.

I am not in your research area. I can only propose some possibilities. If you look at the following descriptions in Fluent help, you might get some ideas. Of course, adding mass source will affect the velocity field. You can try if it works on your case. Good luck.:)

Yuting

Important: Note that if you define a mass source for a cell zone, you should also define a momentum source and, if appropriate for your model, energy and turbulence sources. If you define only a mass source, that mass enters the domain with no momentum or thermal heat. The mass will, therefore, have to be accelerated and heated by the flow and, consequently, there may be a drop in velocity or temperature. This drop may or may not be perceptible, depending on the size of the source. (Note that defining only a momentum, energy, or turbulence source is acceptable.)

Weiqiang Liu July 23, 2019 22:43

Quote:

Originally Posted by Yuting (Post 739806)
I am not in your research area. I can only propose some possibilities. If you look at the following descriptions in Fluent help, you might get some ideas. Of course, adding mass source will affect the velocity field. You can try if it works on your case. Good luck.:)

Yuting

Important: Note that if you define a mass source for a cell zone, you should also define a momentum source and, if appropriate for your model, energy and turbulence sources. If you define only a mass source, that mass enters the domain with no momentum or thermal heat. The mass will, therefore, have to be accelerated and heated by the flow and, consequently, there may be a drop in velocity or temperature. This drop may or may not be perceptible, depending on the size of the source. (Note that defining only a momentum, energy, or turbulence source is acceptable.)

Hi Yuting,

Thanks very much for your suggestion. I've been working on this for weeks and can not find solution. Yes, I have mass source term in the domain. However, I did not define corresponding momentum source.

Thanks very much

Weiqiang


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