Hello,reseaechers
I am doing a case about biomass pyrolysis with 3d dem module, but I’ve been having this problem a lot lately，what is the reason? How should it be solved?
Summary
222.zip (30.3 MB)
Hi, welcome to the MFiX forum.
Thanks for attaching the zip file with your project inputs. However it does not contain log files from your run. If you use the “Submit bug report” menu item from the main menu, it will zip up the log files as well as inputs.
I’m running your case right now to reproduce the error. It’s been running for about 15 minutes without problems. How long did you have to wait until the error occurs?
– Charles
Thanks for your attention and reply very much. I’m sorry I didn’t save the log file.
I ran it nearly 1.5 hours,then this error occured.
After 1.5 hours, it only ran to 0.0013s ,which is probably because my laptop is a bit slow, And sometimes it would quit abruptly without any error. Do you have any idea what might have caused this?
I have tried many times and ended up in these two situations every time. I look forward to your help . Thank you very much!
Unfortunately, debugging support for the Windows platform lags a bit behind Linux, due to the limited set of compiler and debugger tools available on Windows. This is something we are actively working on.
I ran your job on Linux and got the following error trace:
Program terminated with signal SIGFPE, Arithmetic exception.
Typically, SIGFPE happens in user code (UDF) due to division by zero, etc. However in this case it’s happening inside desgrid_mod.f:
#0 0x00007f82615fefd5 in desgrid::jofpos (fpos=-8910716.8078551069) at /home/cgw/Work/NETL/mfix/model/des/desgrid_mod.f:388
388 jofpos = floor((fpos-dg_ystart)*dg_dyinv) + dg_jstart1
None of the variables seem to have problematic values:
(gdb) p fpos
$8 = -8910716.8078551069
(gdb) p dg_ystart
$9 = 0
(gdb) p dg_dyinv
$10 = 257.9999999999996
(gdb) p dg_jstart
$11 = 1
(gdb) p floor((fpos-dg_ystart)*dg_dyinv) + dg_jstart1
$12 = -2298964935
So I’m not quite sure what’s wrong. We will follow up on this issue.
Thanks for the report, and for your patience.
– Charles
Thank you! I will appreciate very much your help！ I will also continue to work on it.
When debugging, my suggestion is to simplify the simulation, and try without any code modification.
Here you modified calc_collision_wall_mod.f and you have reaction rates defined in usr_rates_des.f.
I removed calc_collision_wall_mod.f and it still failed. I set the reaction rates to zero in usr_rates_des.f and it seems to run fine. My guess is one or more reaction rates are too large and it either releases too much gas or decreases the particle diameter too much and some particles shoot out of the domain.
1 Like
Thank you for your advice very much, I will try it.