1. Those that use the physical hypothesis of scale similarity
2. Those derived by formal series expansions
3. Mixed models, which are based on linear combinations of the eddy-viscosity and structural types
4. Dynamic structure models (non-viscosity version)
- R. A. Clark and J. H. Ferziger and W. C. Reynolds (1979), "Evaluation of subgrid-scale models using an accurately simulated turbulent flow", J. Fluid Mech..