Intializing particles with temperature gradient in DEM simulations

MFiX
#1

I am a complete novice at MFIX, so I hope this isn’t too trivial. My aim is to initialize a set of particles in a fluid bed with a linear temperature gradient using a UDF. For now, I’m just creating regions that have particles initialized to different temperatures as such, naturally this is not feasible the finer I want the gradient to be:

image
image1389×899 88.7 KB

I’ve been looking through the user manuals, and forum but haven’t been able to find anything very helpful to this application.

#2

Hi Raghav, welcome to MFiX

Check out the DEM seeding tutorial in particular section 3.22.4

https://mfix.netl.doe.gov/doc/mfix/22.3/html/tutorials/tutorial_dem_seeding.html#reading-initial-particle-data-from-a-text-file

This uses a file particle_input.dat to specify initial conditions on a per-particle basis, which is otherwise not possible in MFiX. You can use a script to generate this file. Note that inn the example, particle temperature is not used, but if you turn on energy equations and set line 29 to T then you can specify initial particle temperature.

– Charles

1 Like
#3

Also covered in more detail in the MFiX FAQ:

https://mfix.netl.doe.gov/doc/mfix/22.3/html/faq.html#how-to-provide-initial-particle-positions-in-particle-input-dat-file

1 Like
#4

Hi Charles,

This helps a lot. Thank you!!

-Raghav