Overview

Simply put, the goal of a mesh convergence study is to verify that enough elements are being used in the model to produce an accurate solution.  This is an important and necessary part of a FE analysis, and without it your analysis will likely be highly inaccurate. FE model predictions are usually “too stiff” when compared to analytical solutions, and it is usually expected that mesh refinement will result in a “softer” solution ^{Anderson-2007}Anderson AE, Ellis BJ, Weiss JA: Verification, validation and sensitivity studies in computational biomechanics. Computer Methods in Biomechanics and Biomedical Engineering, 10(3):171-184, 2007.. Mesh convergence studies usually involve incrementally refining element discretization (i.e. increasing the number of elements) until parameter predictions of interest (displacement, strain, stress, etc.) asymptote(Fig. 1).

There are two types of mesh refinement used for mesh convergences studies: global and local.  With global refinement the number of elements throughout the entire structure is increased, and with local refinement only the number of elements in a region of interest is increased (Fig. 2).

Footnotes

• Anderson-2007
  Anderson AE, Ellis BJ, Weiss JA: Verification, validation and sensitivity studies in computational biomechanics. Computer Methods in Biomechanics and Biomedical Engineering, 10(3):171-184, 2007.
• Ellis-2006
  Ellis BJ, Debski RE, Moore SM, McMahon PJ, Weiss JA: Methodology and sensitivity studies for finite element modeling of the inferior glenohumeral ligament complex. Journal of Biomechanics, 40(3):603-612, 2006.
• Klennert-2017
  Klennert BJ, Ellis BJ, Maak TG, Kapron AL, Weiss JA: The mechanics of focal chondral defects in the hip. Journal of Biomechanics, 52:31-37, 2017.