Files needed for UDFs

[Fei]

Hi everyone,

I have studied “Pulsating 2D fluidized bed” (3.11. Advanced Tutorials — MFiX 21.3 documentation) in MFIX tutorial. In this tutorial, some files are provided to generate pulsating inflow boundary condition. I know the data_kf_0001.txt file need to be written by ourself. But there are some other .f files in this case. My questions are:

(1) How do I know what files (for example, data_kf_0001.txt, usr_mod.f, usr0.f, usr1.f, usr_init_namelist.f and usrnlst.inc in “Pulsating 2D fluidized bed” case) are needed if I want to embed UDFs to realize one function?

(2) Where can I find those essential files, for example usr_mod.f, usr0.f, usr1.f, usr_init_namelist.f and usrnlst.inc in “Pulsating 2D fluidized bed” case.

[cgw]

Hi Fei

1. UDFs are explained in the manual in section 8.2
   https://mfix.netl.doe.gov/doc/mfix/21.3.2/html/reference/user_defined_functions.html

2. The usr_* files are part of the MFiX source. You can find the master copies using the “Editor” pane. Then the “copy” button copes the file to the project directory, where you can edit it.

[Fei]

Thank you Charles. I have a supplementary question. In the tutorial “Pulsating 2D fluidized bed”, the texts written in files like usr_mod.f and usr0.f are not the same as those in the “Editor” pane. This means I have to edit them according to the function expected to be realized. So are there any further tutorials about other UDFs, such as physical parameters, interfacial forces (drag force, lift force, turbulent diffusion force) and mass transfer like evaporation? In this way, we can be more familiar with UDFs.