Learning Forum

[farnazhd66]

Good morning,

after I set all the parameters, I have got 6 information in my physic part. 3 of them are related to mesh based defeaturing. It is written" number of faces have no mesh due to mesh based defeaturing.the faces will be ignored in the solution. available if the filter is off in the additional setting in the Mesh setting". But if I set it to off, I get an error in meshing. what is this mesh based defeaturing and how can I solve it?
because it seems that without solving them, the physic is not solved. 

thanks for your help,

Farnaz

[Gaurav Sharma]

Hi farnazhd66

AIM defeatures small features and imperfections in the geometry (“dirty” geometry) automatically according to criteria you specify. When Mesh based defeaturing is enabled, features smaller than or equal to the Defeaturing tolerance value are removed automatically. The defeaturing tolerance can either be automatically determined or specified by user. If you select "off" no defeaturing will be performed.

It seems your geometry need some cleaning and that is why defeaturing is affecting you. I would recommend:

1. Go ahead with automatic defeaturing and review the mesh generated to verify there isnt ant critical face that has been removed.

2. If there is some face that you wish to retain but has been removed due to defeaturing, you can go for user specified tolerance value and tighten the tolerance to ensure that only unwanted features are removed.

Though you haven't mentioned what error message you are getting with meshing  while defeaturing is off, it seems due to the imperfections in your geometry, mesher might be failing to process the mesh.

Please give a try to the options I have suggested above and do let me know if you seek any further help.

Thanks & Regards,

Gaurav

[farnazhd66]

hi Gaurav,

many thanks for your quick and informative reply. That's true, my geometry has too many details that were affected by defeaturing.

 I tried your suggestions and after automatic defeaturing, set the tolerance value from 0.000735 to 0.000335 and I got an error regarding lack of memory! then I put it to 0.000535 and mesh was updated successfully. one of the warnings is solved but there are still two others about mesh based defeaturing.

the physic still is not being solved:/

do you suggest lower tolerance value or I should try to edit the geometry anyway?

thanks a lot,

Farnaz 

[Gaurav Sharma]

farnazhd66 

Its always better to have a clean geometry to start with. Defeaturing can be thought of as an additional check that may help in fixing a few things that might have been missed at the CAD level.

If there is a significant amount of stuff that needs to be cleaned, my recommendation would be to resolve it at CAD level and leave only a little that you may miss for further defeaturing at meshing level.

Also, since you have already tried whatever possibly can be done by defeaturing (controlling tolerance) and since the problem is still there. It is recommended to go back and perform a clean up the geometry.

Thanks & Regards,

Gaurav