[hamedc]

Hello,


I came across this warning during my closed simulation at commencing start of injection. I’ve checked the location and orientation of injector and nozzle, respectively, and found that those parameters are OK. I think it is related to mesh while the sector was created by in-built sector tool in CONVERGE. How can I fix this warning?
My sector has a step for the lifting hole at center of cylinder axis to mimic the actual piston crown. I think it’s related but I don’t how to fix it (by refining mesh at this location or…).
The next question is how much does this warning affect the accuracy of the simulation?


Thanks,

[lmy_csi]

Hi Hamed,

This warning is likely caused by a highly-skewed mesh near the domain boundary. Sometimes, the cell pairing process in CONVERGE can generate very-skewed boundary cell with the cell center located outside of the domain. In this scenario, parcels can travel across the boundary, and once CONVERGE detects a parcel moving outside of the domain, it will remove the parcel.

Our suggestion is to check the "converge.log" file first, where it logs down the removed parcel mass and the cumulative removed mass every time. If the removed parcel mass is not significant, you can simply ignore it. However, if the removed parcel mass is significant (> 0.1% of the total injection mass), then actions should be taken to carefully improve the boundary cell quality.

Please let me know if you have any other questions.

Thanks,
--Mingyi
___________

Mingyi Liang
Research Engineer, Applications
CONVERGECFD

[hamedc]

Hi Mingyi,


Thank you for your response.

In “converge.log”, I can't find the removed parcel mass and the cumulative removed mass. The full-length warning is “WARNING: [ 531] Found a parcel outside the domain. Removing parcel. This WARNING will only be printed once”.



Thanks,

[lmy_csi]

Hi Hamed,

For the "Screen print level" under Run parameters -> Misc. in Converge Studio, which option do you use? I suggest using "More verbose", which prints the most comprehensive information in the "converge.log" file. You can also make this change in "inputs.in" file by changing the "log_level" to be 3.

Please let me know if this solves the problem. Best of luck!

Thanks,
--Mingyi
___________

Mingyi Liang
Research Engineer, Applications
CONVERGECFD