Refining the Mesh Adaptively Using Error Estimates

Error estimates can be used to automatically place mesh refinement rules (point refinement) in the model where the error is estimated to be large. Refining the model in the areas with the largest errors results in a model where the errors are comparable everywhere in the model and produces a model with increased accuracy without an excessive increase in mesh elements.

When a model has error estimates calculated, the error estimates can be used to define mesh refinement rules. The model is then solved again and new mesh refinement rules are added where the estimated error is large. This process is repeated until the model has sufficiently been refined. It is recommended that you perform mesh convergence tests to confirm that the model is sufficiently refined to produce the required level of accuracy.

The steps required to add additive mesh refinement points using error estimates follows:

  1. Add an error estimate calculation request.
  2. Specify the frequency or apply local mesh settings to allow the automatic mesh algorithm to calculate and mesh the model.
  3. Save the model.
  4. Run the Solver to obtain a solution.

    Figure 1. The result of the error estimation request viewed in POSTFEKO (with a cutplane) indicating the areas with the highest errors in red.

Add an adaptive mesh refinement rule.

  1. On the Mesh tab, in the Refinement Rules group, click the  Adaptive Mesh Refinement icon.

    The error estimate data (in the .bof file) is then matched with the mesh elements (for example, triangle, segments) information (from the .fek file) to calculate the areas where the errors are estimated to be the highest.

    The actual point refinement rule is added to the model tree (Configuration tab) and is indicated by the icon.

    Figure 2. The mesh is refined in the areas where errors are estimated to be the highest. The transparent green spheres are a display setting and indicate areas where the mesh refinement is applied.
  2. [Optional] Multiple iterations of adaptive mesh refinement can be applied by repeating Step 4 to Step 5 for each iteration.
    For each iteration, an adaptive mesh refinement rule is added to the model tree (Configuration tab).

[Optional] Hide the display of mesh rules in the 3D view.

  1. On the 3D View context tab, on the Display Options tab, in the Entity Display group, click the  Meshing Rules icon.