Simulation is not running; solver stops immediately after a few seconds

MFiX
#1

Good day, everyone.

I’m running a TFM 3D simulation for Riser. My .mfix file may be seen here. The build is completed, but the run has come to an end. I’m not sure why the run comes to a halt after a few seconds. There are no errors displayed. The comsole frequently displays the following prompt.

At line 735 of file C:\Users\Admin\miniconda3\conda-bld\mfix-solver_1627537308023\work\model\cartesian_grid\get_cut_cell_volume_area.f
Fortran runtime error: Index ‘1044280896’ of dimension 1 of array ‘list_facet_at’ above upper bound of 653184

Please try running the given file and let me know anything goes wrong. I am using version 21.2.
Please advise me on how to resolve this.
I appreciate any help you can provide.

RISER !.zip (40.2 KB)

#2

First, please update to the latest version of MFIX.

The STL file has lots of thin triangles. Some of them are excluded:

 STL file(s) successfully read.
 Total number of facets read =   230
 Number of valid facets      =   222
 Number of ignored facets    =     8

You can set the facet angle tolerance to zero but it is better to no have those bad triangles in the first place. You should use the procedural geometry to generate clean cylinders.

#3

Dear Jeff

Thank you very much for responding so quickly.

MFiX 22.1.1 available for download
#4

Hello Jeff

I’m having problems with the geometry and flip normal options. Could you possibly advise me on how to resolve this?
Thank you in advance.

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1979×654 38.1 KB

2
21236×643 39.8 KB

riser_2022-03-29T110636.774538.zip (477.8 KB)

#5

Hi Rabindra -

The message "vtkWidget object has no attribute “set_unsaved_flag” indicates that unfortunately there is a small bug in the 22.1 version which got past our testing. We will release a fix for this but in the meantime you can work around this error by opening the file

C:\Users\Energy\anaconda3\envs\mfix-22.1\lib\site-packages\mfixgui\vtk_widgets\modeler.py

in a text editor, and comment out the offending line 1409:

    if not loading:
        # self.set_unsaved_flag()
        self.update_normals()
        self.render()

Please let us know if this solves the problem.

Thank you for reporting this, and sorry for the inconvenience

– Charles

#6

Hello Charles -

Thank you very much for responding so quickly. Yes, the bug has been fixed, and there are no longer any issues with the geometry, but I’m still having issues with the flip normal option.

I’ve attached the document. Could you please explain me what the issue is?

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riser4_2022-03-30T102632.295966.zip (13.4 KB)

#7

I ran this case and it seems to run to completion (t=5s)

Timestep walltime, fluid solver:    0.000 s
 t=    5.000044 Wrote SPx: 1,2,3,4,5,6,7,8,9; .RES
 Total CPU used = 8.850 s
 Total CPU IO used = 0.2583 s
 Total wall time used = 18.81 s

What problem are you having?

#8

Good day, Charles.

Thank you very much for all of your help. Because MFiX- 22.1 occasionally exhibits bug issues, I was unable to run the simulation. There was no problem after closing down and restarting the software.
I’m now able to perform the simulation.