Turbulence Modeling for CFD Simulation

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