Hi All

I work with geometries which have a lot of fillets, which need to be post processed for stresses.

So for convenience I use membrane elements (M3D6), these help me to quickly post process the stresses. What it basically does is it uses the nodes from the solid elements and creates a layer of  elements (M3D6) of a specified thickness (I usually give it a thickness of 1micron so that my stresses are not effected).

But recently I have found that there is a difference in the values of the stresses shown by membranes vs solid elements (almost 60Mpa) at a particular fillet, there is a press fitted pin near this fillet location.  

Solid elements – C3D10

Membrane – M3D6

(Same Material assigned to both of them)

Please let me know if anyone has faced similar issues and if membranes are recommended for post processing stress values

Do let me know if you need more information

Thanks