Laminar equations only, no turbulence model

Less time per iteration due to fewer equations


Modified k-ω URANS, no subgrid-scale modeling


Hybrid but no subgrid-scale model

Dynamically resolves structures based on von Kármán length scale

Most stable scale-resolving model, but can remain in URANS for mildly separated boundary layers and undisturbed channels with lower instability


Hybrid with subgrid-scale model

Shielding (blending) between zones

Grid-induced separation mitigated, but possible

Asymptotic shielding, preserves νt.

Requires strong instability to activate LES

Superseded by SBES


Hybrid with subgrid-scale model

Improved shielding (blending) between zones includes shear stress term

Faster transition to LES in separating shear layers

Relatively new, limited published research

Zonal LES

Hybrid with subgrid-scale model in explicitly defined zone

Transition from modeled to resolved turbulence

RANS and LES zones must be defined by user

Synthetic turbulence model required at RANS-LES interface