Is it converging???

ghorrocks · February 4, 2019, 17:25

By definition a mesh sensitivity analysis is running the simulation on different meshes. So you cannot avoid running many different meshes.

Here are some useful references for basic analyses:
https://caeai.com/blog/how-do-i-know...sh-good-enough
https://www.computationalfluiddynami...pendent-study/

More advanced techniques are here:
https://journaltool.asme.org/Templat...umAccuracy.pdf
The textbook "Computational Fluid Dynamics" by Roache, and
The Richardson Extrapolation technique (look it up)

NewToAnsys · February 5, 2019, 06:36

Thank you Mr. Horrocks, that really helps! A couple more questions:

1. So then my project schematic would look like the attached picture?
2. I'M using a student license and no Adaptive Sizing. I have a number of local refinements defined. So how do I globally refine the mesh? There seems to be no 'Refinement' option in the global controls when my adaptive sizing is off.

Thanks a lot for your time!

ghorrocks · February 5, 2019, 18:00

You schematic looks OK.

When I do mesh refinement if possible I halve the length of all edge length definitions, both global parameters and any local refinement. If that is not possible then you halve the element edge lengths in the critical areas but this does compromise the analysis somewhat.

NewToAnsys · February 7, 2019, 04:46

Great, Thanks a lot!

February 4, 2019, 17:25		#101
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,872 Rep Power: 144	By definition a mesh sensitivity analysis is running the simulation on different meshes. So you cannot avoid running many different meshes. Here are some useful references for basic analyses: https://caeai.com/blog/how-do-i-know...sh-good-enough https://www.computationalfluiddynami...pendent-study/ More advanced techniques are here: https://journaltool.asme.org/Templat...umAccuracy.pdf The textbook "Computational Fluid Dynamics" by Roache, and The Richardson Extrapolation technique (look it up) __________________ Note: I do not answer CFD questions by PM. CFD questions should be posted on the forum.

February 5, 2019, 18:00		#103
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,872 Rep Power: 144	You schematic looks OK. When I do mesh refinement if possible I halve the length of all edge length definitions, both global parameters and any local refinement. If that is not possible then you halve the element edge lengths in the critical areas but this does compromise the analysis somewhat. __________________ Note: I do not answer CFD questions by PM. CFD questions should be posted on the forum.

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February 7, 2019, 04:46		#104
NewToAnsys New Member Join Date: Oct 2018 Posts: 17 Rep Power: 8	Great, Thanks a lot!