How can i prove, that a DNS was correctly done. I found the following by searching this forum:

"The usual test for a fully valid DNS simulation is to check that no energy is aliasing back from the highest resolvable wavenumbers and distorting the low wavenumbers. This is a nice simple mathematical test equivalent to saying that the Kolmogorov scales (all the scales) are fully resolved."

I must confess, I am a CFD beginner. So maybe there is an easier to understand answer.

Thanks, Dirk

Hi,

For several flow geometries (channel flow, isotropic turbulence etc.) there exits rules of thumb for the spatial resolutions. These you can find in the literature. But the spatial resolution is not the only important issue in DNS. Boundary and initial conditions and the domain size (the domain should be large enough to capture the largest scales) play also a crucial role.