Turbulence Modeling for CFD Simulation

GEKO puts you in control of turbulence

Since no single turbulence model is suitable for all flow applications, users must choose from a finite set of fixed models, hoping that one fits their simulation. Introducing GEKO (Generalized k-omega), a revolutionary concept in turbulence modeling that provides users with the flexibility to tailor turbulence models to their applications. Developed by turbulence expert Dr. Florian Menter, GEKO provides several free and tuneable parameters, which can be adjusted over a wide range to match the simulation to specific physical effects, while maintaining the underlying calibration for flat plates and mixing layers.

In computational fluid dynamics (CFD), even simple flows are difficult to compute. And, the computational complexity grows exponentially when accounting for turbulence: irregular fluid motions that span a wide range of scales in space and time.

Selecting the right method for modeling turbulence physics is critical … and confusing. While turbulence can be fully described by the Navier-Stokes equations, direct numerical simulation is impractical due to massive resource requirements. So how do you choose from among the many available turbulence models to meet your design-specific challenges? With expert guidance. ANSYS offers a variety of simulations — comprising a wide range of model formulations and strategies — plus the comprehensive selection support to ensure your solution delivers the accuracy you need.

Learn how turbulence model selection can impact simulation accuracy — even for seemingly simple applications. Turbulence is a critical computational fluid dynamics (CFD) app that you must get right.

Read the application brief: The Challenge of Turbulence in CFD Simulations

Turbulent Flow Simulation Methods

DNS

Calculates the exact turbulence solution, but is too computationally intensive to be practical.

  • Numerically solves the full unsteady Navier-Stokes equations
  • Useful only as a research tool

SRS

Delivers the greatest accuracy for real-world computing capacities.

  • Directly calculates the motion of the largest turbulent eddies in at least a portion of the domain
  • Especially suited for large-scale separations, strongly swirling flows, acoustics, etc.
  • Large eddy simulation (LES) models included in this category

RANS

Good enough solution for many industrial flows.

  • Time-averaged solution “smooths” turbulent eddies
  • Requires least computational power