Accuracy of simulations

Altair Forum User

How can I know the accuracy of my predictions or the range of error that my co-efficients of lift and drag?

acupro

The only way to know with certainty is to compare to experiments with absolute certainty - which never really exist either.  The best one can do with simulation tools is to perform sensitivity studies and see how results of interest change while something about the simulation is changed.  This would include mesh sensitivity (first layer height in boundary layer, surface mesh size, volume mesh size, etc.), sensitivity to level of convergence achieved (residual ratio, etc.), boundary condition sensitivity (velocity, turbulence, surface roughness etc.).  Once one has determined the solution is no longer sensitive to changes in these various aspects, the solution is as good as can be achieved with the simulation tool.