Turbulence is the usual state of motion of fluids except at low Reynolds numbers. Understanding its physics is essential in a wide range of scientific disciplines, including engineering, progress in renewable energy, aerodynamics, astrophysics, geology or weather prediction. The governing equations for both laminar and turbulent flows are the same (the Navier-Stokes equations), but the complexity of turbulent flows is very high so huge computational resources are needed to proceed to their direct solution without any model. This approach is known as Direct Numerical Simulation (DNS). DNS is important for shedding light into the complex physics of turbulent flows, as well as to provide data for the development and validation of turbulence models (both Large Eddy Simulation (LES) and Reynolds Averaged Navier-Stokes (RANS) models) and also to be directly applied to certain types of flows. CTTC has developed parallel high performance software, that can run efficiently on thousands of processors, and used it to carry out several large scale DNS and LES simulations, such as the examples presented in this page.

Examples:

Flow past a circular cylinder from critical to trans-critical Reynolds numbers

Numerical simulations of massive separated flows: flow over a NACA airfoil at moderate Reynolds numbers

Direct Numerical Simulation of turbulent flows in bodies of revolution using unstructured meshes. Flow past a sphere at subcritical Reynolds numbers.

Direct Numerical Simulation of turbulent flows in complex geometries using unstructured meshes. Flow around a circular cylinder at subcritical Reynolds numbers.

Direct Numerical Simulation of  Buoyancy-Driven turbulent flows.

Turbulent flow through a Square Duct: Direct sumerical simulation and advanced turbulence modeling

Direct numerical simulation of a turbulent plane impinging jet

Supersonic Turbulent Flow Past a Circular Cylinder