Comsol: Utilizing Symmetry Planes for Finer Grid

[lucky_1809]

Hi
I realize a model that requires a very fine grid in comsol, so i have reduced the DoFs using symmetry planes. My structural model has 2 symmetry planes, so i have built a quarter of the total model, but now I don't know the way to tell to comsol that the realized model is only a quarter of the total...help me please!

 

[sunset451]

what is the phisics of your subdomain? I use a symmetry boundary condition for a fluid and plane symmetry (corrisponding to the goemetry plane's symmetry) for a solid.

 

[lucky_1809]

hello, forgive me for the delay in the answer but i was on holiday in cyprus, very beautiful place...My model is structural model with solid subdomain and shell subdomain, and I want to find eigenfrequencies... I tried to find eigenfrequencies in 2 ways...I realized the global geometry and after a slowly processing i found eigenfrequencies that are about the frequencies founded in experimental activity(the first f = 3.5Hz)..after i have built a quarter geometry and I put symmetry constraints like you told me, but I found very high frequencies (the first f = 1345 Hz). I supposed that comsol considers this constraints in a wrong way like an external constraint and not a symmetry plane.thank you