The basic idea of LES is that large eddies, which are highly irregular and strongly dependent on the flow problem, cannot and should not be modeled, but the much more universal small eddies might be modeled successfully. The method uses a spatial averaging of the velocity field to resolve only the large eddies containing the majority of the turbulence kinetic energy. The dissipative effects of the small eddies are reproduced by relatively simple algebraic models, e.g. WALE (Wall-Adapted Local Eddy Viscosity). LES performs generally better than conventional CFD methods and bears less modeling uncertainties.