Fluid bed drying simulation

Submitted by syedUConn on Thu, 06/13/2019 - 19:09

Hi,
For my project, I need to make a model of fluid bed drying. I have hot air coming in from the bottom and heating wet particles and eventually drying the particles. For this, I could run the simulation up to the heat transfer from the fluid to the particle, which is pretty straightforward and a lot of tutorials helped me. But, now I am really stuck as I need to incorporate moisture in particles and simulate drying. My first idea was to use cfdemSolverPisoSTM and consider the moisture as species but I do not know what is speciesCCapacity and how can I relate this parameter to the drying rate. So I could not go anywhere.
Then I thought of using the easo capillary model. I incorporated the model as specified by the documentation. But I receive the following error (as I need to know the liquid content and how it varies with time),

dump dmp all custom 20000 ../DEM/post/dump*.liggghts_run id type x y z ix iy iz vx vy vz fx fy fz omegax omegay omegaz radius f_Temp[0] f_heatFlux[0] f_surfaceLiquidContent[0]
ERROR: Could not find dump custom fix ID (../dump_custom.cpp:1384)
(../dump_custom.cpp:1384)

Also before the error, I receive the following warning,

WARNING:
The contact model you specified is not located in any whitelist.
Because of this the model will be run in an unoptimized version (increasing runtime by up to 20%).
In order to optimize this model you have the following options:
(i) Run the genAutoExamplesWhitelist.sh script in your LIGGGHTS(R) source folder to automatically parse the input script
(ii) Add the model combination by hand to your style_contact_model_user.whitelist that can be found in your LIGGGHTS(R) source folder
If you perform one of the steps above LIGGGHTS(R) needs to be recompiled to generate the optimized code.

(../contact_models.h:364)

I will really appreciate if someone can give some input for this.

Thanks in advance

vanamu | Fri, 07/09/2021 - 15:22

WARNING:
The contact model you specified is not located in any whitelist.
Because of this the model will be run in an unoptimized version (increasing runtime by up to 20%).
In order to optimize this model you have the following options:
(i) Run the genAutoExamplesWhitelist.sh script in your LIGGGHTS(R) source folder to automatically parse the input script
(ii) Add the model combination by hand to your style_contact_model_user.whitelist that can be found in your LIGGGHTS(R) source folder
If you perform one of the steps above LIGGGHTS(R) needs to be recompiled to generate the optimized code.

(../contact_models.h:364)

mschramm | Fri, 07/09/2021 - 21:10

Hello,
The above is not an error. It is simply telling you that the specified model is not running in the most optimal state.
If you would like the warning to go away, you will need to add your specific model combination to the whitelist in src and recompile your liggghts code.

Akanksha Rajput | Tue, 11/21/2023 - 15:29

dump DUMP1 all custom 500 ../DEM/post/dump.liggghts_run id type x y z vx vy vz fx fy fz f_dragforce[1] f_dragforce[2] f_dragforce[3] radius f_surfaceLiquidContent[0] f_liquidFlux[0] f_liquidSource[0]
ERROR: Could not find dump custom fix ID (../dump_custom.cpp:1384)

I am getting the abovementioned error while trying to dump f_surfaceLiquidContent[0] in a CFDEM simulation. The simulation runs fine till I add "f_surfaceLiquidContent[0] f_liquidFlux[0] f_liquidSource[0]" in the dump command.
Can anyone please explain how I can dump the liquid content?