When I ran the variable density model in MFIX21.1.4, I found two keywords defined under the Advanced button.
I want to know why the values for these two keywords are defined and how to do it. I know that 0.6 is the maximum volume fraction of solids.
variable_density.zip (7.9 KB)
@cgw @jeff.dietiker
The “Advanced” tab is used to set up MFiX keywords which are otherwise not exposed in the GUI. The MFiX backend code (Fortran solver) has been around a long time and is very large, not all of its keywords are connected to controls in the GUI. The GUI attempts to make it easy to set up and run the most common types of MFiX simulations but sometimes it’s necessary to set up additional keys in Advanced. This is also where any user-defined (UDF) keys appear.
To add a keyword in this section, click on the ‘+’ button. To edit the value of one that is already set, either double-click the row, or select the row and click the “edit” (pencil) icon.
I’m not completely sure why these ep_s_max keys are set for the variable density tutorial - I did not create this tutorial. But you could try unsetting the keys, or changing their values, and see what effect that has.
– Charles
I noticed that there is a small bug when trying to modify the values of the ep_s_max key in the Advanced pane. This is due to a problem in the range checking code, which will be fixed in the next release. For now, you can work around this by editing the file init_namelist.f in the MFiX source directory and changing line 1719 from
! <range min="0" max="1-EP_STAR" />
to
! <range min="0" max="1" />
– Charles
Thank you Charles， you helped me out.