DEM-Fluidized bed simulation not running

MFiX
#1

Dear experts!
I am trying to reproduce the research paper http://dx.doi.org/10.1016/j.ijheatmasstransfer.2017.04.040. I set all the parameters accordingly.
At first I calculated the minimum fluidization velocity which is according to paper. I set all the parameters according to paper.

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image708×755 104 KB

But my simulation didnot run. My case attached in zip file.
Your kind insight required to resolve the issue.
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selfbd.zip (17.2 MB)

#2

Please define your boundary walls and understand the geometry better to accurately model the fluidization behavior.

I have attached a few screenshots from my simulation case. Will be happy to help if you cannot figure it out.

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Best,
Ashreet Mishra.

1 Like
#3

Dear Mishra!
I tried a lot and set BC according to the paper but my simulation did not run. There is some error that I can’t figure out so far.
Your guidance will be highly appreciated in this regard.
I am looking forward to learning.


2nd.mfx (14.7 KB)

#4

Dear,
Hope you are fine! I need your guidance in the above problem.
Will be very thankful for your kind support.

#5

Hello @majidkhalil,

I apologize for the delay. I will send you my source files according to the paper in a couple days which you can use to learn how to build both the thermal and flow models.

Regards,
Ashreet Mishra.

1 Like
#6

test.zip (27.3 MB)
Attached is the working file, please try to relate that to the paper and let me know if you have any questions.

Regards,
Ashreet Mishra.

1 Like
#7

Daer @ashreet
First of all bundle of thanks for your kind support.
When I start the sim, it prompts the error dt<dt_min, after that I, modify the time step, then it works smoothly, Still result comparison remaining.
I have a few queries regarding the parameters,

  1. Bed height is declared as from ymin to ymax/2, but in paper bed height is not mentioned, how do we select it?
  2. How do we compute different heat transfer mechanisms via MFiX-GUI? such mention in the paper
    image

Thanks.

#8

Hello @majidkhalil,

Yes the time step is something you need to use from the reference paper. I used a higher time step to debug the code and test it.

  1. It is one of the assumptions I have made since bed height is not provided either in that ref or Patil et al. I mean you can parametrically study how much the results change but using those settings I was able to get good validation.

  2. You can refer this thread (The User Variables output run with DMP - #3 by ChenYuan1), that is something I am not very familiar with. You can let me know if you can figure it out :slight_smile:

Best,
Ashreet Mishra.

1 Like
#9

Hello @ashreet
Hope you are doing well.

Now I move further, used the same geometry and sim paratmers, proceed with non spherical particles with an aspect ratio 5/4.
I test the sim without checking the energy equation. And I have the error
image

In this regard, your kind attention will be very helpful to me.

My project zip is attached for your reference.
1000p.zip (27.8 MB)

#10

Hello @majidkhalil I am not experienced with SQP-DEM. Maybe someone else can help you out with that.

Regards,
Ashreet Mishra.

1 Like