Verification and Validation

Now that we have our results, it is important that we check to see that our computational simulation is accurate. One possible way of accomplishing this task is comparing to the pre-calculations, as we did in the results section. Another way to check our results is by refining the mesh further. The smaller the elements in the mesh, the more accurate our simulation will be, but the simulation will take longer. To refine the mesh, look to the outline tree and click Mesh > Face Sizing Change the element sizing to .25 (half the size of the mesh we originally tried). The new mesh looks like this . It has twice as many elements as the original.

Now hit solve. Compare the values for your stresses with those we found for the original mesh. Are the very different? Or do they seem to approach a limit? If the latter, the mesh is refined enough and if you modeled the problem correctly, you are done! Below are the values from our original mesh, followed by the values for our refined mesh.

As one can see from the table above the results do not change as the mesh is refined. The reason that the results do not change is that they have already converged to the answer. The exact solution for the deformation is cubic and for this setup ANSYS uses element BEAM 188 which in turn uses cubic interpolation. Thus, for the simple cantilever beam setup the numerical method converges very quickly.