Pulsating fluidized bed

MFiX
#1

Dear developers! I recently worked on a pulsating fluidized bed, which I used as a DEM model. I learned the advanced tutorial, but when I imitated setting multiple different gas mass inlet boundaries, only the gas inlet with BCID=1 corresponded to data_kf_0001.txt, and the rest of the mass inlet did not have gas pulsatile inflow, which confused me. (Also set BCID=2 and data_kf_0002.txt and),can you give me some advice? looking forward to your reply， Thank you very much!

The chemical reaction in the simulation was not carried out
#2

Please make sure you:

  1. Set a value for bc_v_g(2) in usr1.f and verify it is changing with time (with a print statement).
  2. Broadcast the value of bc_v_g if you are running in parallel (DMP).
  3. Call set_bc0_vel_inflow(2) to apply the change.
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#3

Hello developers, your suggestion is very useful, it can run successfully. Thank you very much for your help! I want to use a sinusoidal flow at the inlet, as in the following formula. But the advanced tutorial doesn’t say how to do it. Can you give me some guidance? Best regards! Looking forward to your advice and guidance！
image
Where Ubg represents the average gas velocity. Us and f are the amplitude and frequency of the pulse flow, respectively.

#4

You can either discretize your sine wave and store it into data_kf_0001.txt or code the sine wave in usr1.f instead of reading keyframe data.

#5

Hello! Dear developers! 2.Broadcast the value of bc_v_g if you are running in parallel (DMP). I don’t quite understand the second one. Could you elaborate on it? I am now going to use DMP for calculation, but the following error occurs. Please give me some help and look forward to your guidance!
image

#6

If you are using keyframe data, look at the pulsating fluidized bed tutorial. This one is set up to run in serial only. If you want to run it in DMP, the inlet velocity needs to be broadcasted to all processes because the keyframe data is interpolated on the head process (process 0). This is done with the call to bcast:

call bcast(bc_v_g(i))

After this call, all processes will know the new value of the inlet velocity.

Please see the attached file:
usr1.f (3.0 KB)

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