Dear Expert,
Could you tell me, which drag model is used between the particle-particle in TFM? when I use two different particles in the TFM then how can I define the drag model between the two particles? Also, how can I calculate the particle-particle heat transfer coefficient?
which equation used Mfix between the particles? and where it is defined in the Mfix?
Dear Expert,
I have found the one article that gives particle-particle heat transfer in the MFix manual. please see it and let me know that how can i applied in the mfix for the simulation.
Syamlal, M., 1987, “The Particle-Particle Drag Term in a Multiparticle Model of Fluidization,”
Topical Report, DOE/MC/21353-2373, NTIS/DE87006500, National Technical Information
Service, Springfield, VA.
Sorry about this. This is not what I mean. I thought the experts knew the field behind it, even this equation I was asking three days ago.
Thank you for your patience. There is no specific setting for the solids drag. The formulation is the one in the report your found and it is automatically applied.
Thank you for your reply. As I checked in the Mfix manual solid-solid particle drag force equation is there, if it exited in the manual then it is also applied in the simulation. I found it in the mfix editor box ( SUBROUTINE DRAG_SS(L, M)), do you know where it is applied?
also attached is the particle-particle heat transfer coefficient, kindly look at it.
and if it is applied then how can i find the solid-solid heat exchange coefficient?
also if the calc_gama.f is define for the gas-solid heat transfer then what will be solid-solid exchange coefficient?
If you have this article PDF please share it. I have it but the quality of the PDF is not good.
M. Syamlal, The particle–particle drag term in a multiparticle model of fluidization, National Technical Information Service, Springfield, VA, 1987 (DOE/
MC/21353-2373, NTIS/DE87006500)
The solid-solid drag is applied in the momentum equation. This is only applied between two different solids phases.
The solids-solids heat conduction between two different phases is neglected in TFM. I don’t know where you got Eq. 28-29 from but it looks like DEM.
Dear Jeff.
I am solving this problem binary mixture (two solid) particles only. Therefore I want to apply the drag model and calculate the heat transfer coefficient between the two solids.
Equations 28-29 used the heat transfer coefficient between the two solid particles in the computation study and found in the article which is attached herewith.
Have you said that this problem will be solved by DEM and not is the TFM?
I cannot say if you should use TFM or DEM. It depends on the inventory (i.e. how many particles you have) and you computational resources.
I refered one of the Article which is solved this problem in the fluent, and solid pack bed heights is given not given the no. of particle. I think this problem can be also solve in TFM, i saw the drag force (drag.ss) in the editor box, but i didn’t find heat transfer between the solid-solid.
Please check Syamlal article 1986. That given equation.
My system having 32 gb ram, and 24 core, 8 gb Graphics.
As I said earlier, the solids-solids heat conduction between two different phases is neglected in TFM, there is only conduction within a given solids phase. The Syamlal report does not discuss heat transfer, only drag. Eq. 28 and 29 are not from the Syamlal report.
I follow this article. this problem is solved in the fluent.
https://www.sciencedirect.com/science/article/pii/S0032591011005511
If the solid-solid drag coefficient is exited then heat transfer also exiting, Could you tell me, if it will solve or not in the Mfix, if yes then what should I do DEM or TFM?
I don’t understand what you mean by:
If your goal is to run TFM with solids-solids heat transfer (between different solids phases) to reproduce the article’s results, then you should use Fluent. The equations you are referring to is what Fluent solves, not MFiX.
Dear Jeff,
Here I want to know that, if I am using Mfix and taking two solid particles and want to calculate the heat transfer between the phase (gas-solid) and (solid-solid), it will use DEM, not TFM?
it means mfix can calculate the heat transfer between the solid-solid phase, forgetting about the fluent equation and method.
Yes, there is a particle-particle conduction term in MFiX DEM, not MFiX TFM.