Benchmark study among SnS, SW Simulation 2010 and Comsol Multiphysics 3.5a

Hi All,

I made a benchmark study among Scan&Solve and two simulation software I usually use: SolidWorks Simulation (2010, 64 bit) and Comsol Multiphysics (3.5a, 64bit).

The study is related to a vehicle coupler (3D model) with many small features and fillets.

The coupler is fixed in all directions on the ring slot, and pulled along x-axis on both coaxial cylindrical holes with 20kN (applied on half cylinder). Moreover, both inner planar faces of the coupler are constrained in z direction (to simulate the presence of the mate coupler). Steel AISI 1020 material is assumed. See figure.

Some notes:

- In SW Simulation a h-adaptative mesh analysis was performed as previous results were depending strongly from the mesh adopted in the more stressed areas.

- In Comsol some issues were found to mesh the model and a tuning manual set-up of mesh parameters was necessary to mesh small patches.

- In SnS the maximum resolution was set and the element size of the basis functions is much bigger than the average mesh size set in the other software.

- While run time are similar for SW Simulation (about 1 min + 30 sec for meshing) and Comsol (about 2 min + 10 min for meshing), about 6 min where needed for SnS on a notebook (Centrino 2 DUO T9600, 8GB Ram, Win7 64 bit, Rhino V4).

From the comparison one can see the very good agreement between SnS and Comsol results (benchmark_grid), whereas some significant differences arise with SW Simulation. On the other hand, SW simulation is supposed to give the more accurate solution as the mesh improvements are made automatically through the h-adaptative method, not adopted in Comsol. Consider, moreover, that SW and Comsol got the same maximum x-displacement, and displacements are usually considered the more reliable results in contrast with stresses.

While testing SnS I faced out with the following issues.
1) After running an analysis, if I modify the model (just moving a face, for example) and a lunch again SnS on that solid, the software show me previous results and doesn't alert me about variations in the model.
2) SnS should allow to save more analyses carried out on the same model.
3) A multi-resolution is welcome to better adapt basis functions to small geometrical features.

4) Run time can be strongly speed-up on Rhino V5 64 bit version.

Comments are welcome.

Salvatore