Symmetry

Symmetry

Simulation models can be simplified using Symmetry. This is only appropriate if the geometry as well as the loads are symmetrical in the same direction.

There are three different types of Symmetry. Most common is Mirror Symmetry (https://www.fea-solutions.co.uk/mirror-symmetry/), but 2D simplifications (https://www.fea-solutions.co.uk/2d-models/) and cyclic symmetry (https://www.fea-solutions.co.uk/cyclic-symmetry/) are also used.

For Buckling and Modal Analysis (https://www.fea-solutions.co.uk/modal-analysis/), Symmetry should not be used, even if the geometry and loads are symmetric. This is because on a FEA model with symmetry, only symmetric results will be generated, but asymmetric results will not be obtained, which is not acceptable for the analysis types mentioned above.

The primary advantage of using symmetry in a FE model is that the mesh can be finer compared to that of the full model. This will allow simulation run times to remain the same, whilst having a higher numerical resolution. Another advantage is that there is better convergence of non-linearities during the numerical solution, as some rotations and translations are constrained by the symmetry conditions.

With many FEA programs, results from a symmetry model can be displayed as projections on the full model.

Please call us today on +44 (0)1202 798991 for any engineering analysis requirements you might have.