One important aspect of numerical simulations is to check the validity of the solution. Generally, there is not an analytical solution generally available, so the simulation must be checked against itself at a higher resolution. The process of checking a solution at increasing resolution is known as convergence checking, as the solution is expected to converge on a particular value. The convergence checking process begins by picking a stress, strain, or deflection at a point to study.
Generally, the deflection at a point will converge on a consistent solution faster than the stress. This is because the deflections are the fundamental result of finite element analysis, and stresses are then derived from displacements. For this reason, we will be studying the convergence of stress.
The convergence checking process can be automated in SnSScript. The attached script will allow you to run a basic convergence check. Download the script here: Convergence Checking Script
All of the settings (such as chosen resolutions and the value to check) can be changed in convergence.rvb by editing a script.
If you are interested in the process of convergence checking and why this script was created in this way, check out this reference on practical convergence checking.
It is also possible to generate a plot of convergence data using SnSScript. Download the script here: Convergence Plotting Script
The data produced by the script is best plotted with the values of resolution on a logarithmic scale.