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Now how do you know if a simulation is complete? It doesn’t really matter how long a simulation has been running or how many iterations it has completed. What matters is the convergence of the simulation. A common way to track convergence is to plot the simulation residuals at each iteration. SimScale automatically generates this plot and it can be found in the navigation panel, under the run that you started, then under Convergence plots, seen in Figure 3.1. The goal is to have residuals that are as close to zero as possible. They will not actually reach zero though, so you have to end the simulation when you've achieved sufficient convergence. At most, your residuals should be 1e-3 to have any confidence that your results are realistic, ideally they should be in the 1e-4 to 1e-6 range. At residuals of 1e-5 to 1e-6 you can have moderate confidence that your predicted drag and lift values will match the real values (Assuming the rest of the simulation was set up properly).
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