Large eddy simulation

From Glossary of Meteorology

large eddy simulation

  1. (Abbreviated LES.) A three-dimensional numerical simulation of turbulent flow in which large eddies (with scales smaller than the overall dimension of the problem in question) are resolved and the effects of subgrid-scale eddies, which are more universal in nature, are parameterized.

    Large eddies are important in characterizing one turbulent flow from another. The difference between a large eddy simulation and the traditional phenomenological modeling of turbulence is that in the latter case all scales of turbulent motion are parameterized.

  2. A modeling technique in which spatial resolution extends into the inertial subrange, but does not resolve the smallest scales of motion.

    The effects of the latter are approximated using subgrid-scale models, which usually draw heavily on the Kolmogorov theory of the inertial subrange.
    See direct numerical simulation, very large eddy simulation.