Detached eddy simulation

Regions near solid boundaries and where the turbulent length scale is less than the maximum grid dimension are assigned the RANS mode of solution.

As the turbulent length scale exceeds the grid dimension, the regions are solved using the LES mode.

Therefore, the grid resolution is not as demanding as pure LES, thereby considerably cutting down the cost of the computation.

Grid generation is more complicated than for a simple RANS or LES case due to the RANS-LES switch.

DES is a non-zonal approach and provides a single smooth velocity field across the RANS and the LES regions of the solution.