Why can't I find the archive of the source code of some cases of Mfix?

Why can’t I find the archive of the source code of some cases of Mfix?

What are you looking for? This is a very vague question.

I’d like to find some examples of models that your company has already built to learn about Mfix.I followed the instructions in the picture to find some source code, but unfortunately I didn’t find it.

The tutorials included with MFiX are up-to-date. There are additional tutorials in the source tarball, but these are not included with the MFiX distribution because they have various issues - some need to be converted from CGS units to SI, or don’t work for various reasons. If you want to look at them anyway, try this link
https://mfix.netl.doe.gov/products/mfix/mfix-archive/

Are there any tutorial examples on the combustion of solid substances?

legacy_tutorials/SpoutedBedCombustor
Note that this is a CGS case and MFiX no longer supports CGS units. The values in mfix.dat will be automatically converted to SI units, but the values in usr_rates.f need to be converted by hand - this is why this tutorial is not included with the MFiX distribution. If you do the work to convert it to SI please let us know, we could possibly add it to the distribution.