Hands-on turbulence modeling with SGS, DES/IDDES, and real-world CFD case studies
Large Eddy Simulation (LES) is an advanced turbulence modeling approach that resolves large-scale turbulent structures while modeling the smaller scales. Compared to traditional RANS models, LES provides improved predictions for unsteady, separated, and wake-dominated flows, but requires careful modeling choices and mesh design. This course offers a practical and intuitive introduction to LES using OpenFOAM, focusing on physical understanding and correct application rather than detailed mathematical derivations.
What you’ll learn
- Derive the LES formulation from the Navier–Stokes equations using spatial filtering.
- Understand subgrid-scale (SGS) stresses and the physical role of SGS models.
- Implement and compare major SGS models: Smagorinsky, WALE, k-equation, dynamic, and hybrid RANS–LES (DES/IDDES).
- Set up and run practical LES simulations for turbulent flow past a square cylinder.
- Analyze vortex shedding, wake dynamics, turbulence statistics, and mesh resolution requirements.
- Compare LES results with k-ω SST RANS to evaluate accuracy and computational cost.
- Apply guidelines for wall-resolved vs. wall-modeled LES in engineering problems.
Course Content
- Introduction to Large Eddy Simulations –> 1 lecture • 41min.
- Standard Large Eddy Simulations Models –> 4 lectures • 1hr 23min.
- DES, DDES & IDDES with OpenFOAM Implementation –> 1 lecture • 27min.
Requirements
Large Eddy Simulation (LES) is an advanced turbulence modeling approach that resolves large-scale turbulent structures while modeling the smaller scales. Compared to traditional RANS models, LES provides improved predictions for unsteady, separated, and wake-dominated flows, but requires careful modeling choices and mesh design. This course offers a practical and intuitive introduction to LES using OpenFOAM, focusing on physical understanding and correct application rather than detailed mathematical derivations.
The course provides a conceptual overview of how LES is derived from the Navier–Stokes equations, explaining spatial filtering, filter width, and the physical meaning of subgrid-scale (SGS) stresses. The emphasis is on understanding what is resolved, what is modeled, and why SGS models are needed, without going through step-by-step mathematical derivations.
You will learn how different SGS and hybrid RANS–LES models behave in practice, including:
- Smagorinsky, WALE, and k-equation SGS models
- Hybrid RANS–LES approaches such as DES and IDDES
A major part of the course is a hands-on LES workflow applied to a real engineering benchmark: turbulent flow past a square cylinder. Using this case, you will set up and run LES simulations in OpenFOAM, compare different SGS models, and analyze vortex shedding, wake dynamics, and turbulence statistics. All LES results are compared with a baseline k–ω SST RANS simulation to highlight accuracy and computational cost trade-offs.
The course also provides practical modeling guidelines, including mesh resolution requirements, time-step selection, wall-resolved vs. wall-modeled LES concepts, and common pitfalls to avoid. Estimation of turbulence scales and interpretation of LES results are discussed from an engineering perspective.
To support hands-on learning, the course includes complete OpenFOAM case files for all demonstrations, along with additional PDF documents that summarize theoretical concepts, modeling guidelines, and best practices. By the end of the course, you will be confident in setting up, running, and evaluating LES and hybrid RANS–LES simulations for practical engineering applications.