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K-epsilon models

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The K-epsilon model is one of the most common [[Turbulence modeling|turbulence models]]. It is a [[Two equation models|two equation model]], that means, it includes two extra transport equations to represent the turbulent properties of the flow. This allows a two equation model to account for history effects like convection and diffusion of turbulent energy.
The K-epsilon model is one of the most common [[Turbulence modeling|turbulence models]]. It is a [[Two equation models|two equation model]], that means, it includes two extra transport equations to represent the turbulent properties of the flow. This allows a two equation model to account for history effects like convection and diffusion of turbulent energy.
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The first transported variable is turbulent kinetic energy, <math>k</math>.  The second transported variable in this case is the turbulent dissipation, <math>\epsilon</math>. It is the variable that determines the scale of the turbulence, whereas the first variable, <math>k</math>, determines the energy in the turbulence.
The first transported variable is turbulent kinetic energy, <math>k</math>.  The second transported variable in this case is the turbulent dissipation, <math>\epsilon</math>. It is the variable that determines the scale of the turbulence, whereas the first variable, <math>k</math>, determines the energy in the turbulence.
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To define calculate boundary calculations for this model [[Turbulence modeling|Turbulence free-stream boundary conditions]]
== Usual K-epsilon models ==
== Usual K-epsilon models ==

Revision as of 09:11, 15 May 2008

Turbulence modeling
Turbulence
RANS-based turbulence models
  1. Linear eddy viscosity models
    1. Algebraic models
      1. Cebeci-Smith model
      2. Baldwin-Lomax model
      3. Johnson-King model
      4. A roughness-dependent model
    2. One equation models
      1. Prandtl's one-equation model
      2. Baldwin-Barth model
      3. Spalart-Allmaras model
    3. Two equation models
      1. k-epsilon models
        1. Standard k-epsilon model
        2. Realisable k-epsilon model
        3. RNG k-epsilon model
        4. Near-wall treatment
      2. k-omega models
        1. Wilcox's k-omega model
        2. Wilcox's modified k-omega model
        3. SST k-omega model
        4. Near-wall treatment
      3. Realisability issues
        1. Kato-Launder modification
        2. Durbin's realizability constraint
        3. Yap correction
        4. Realisability and Schwarz' inequality
  2. Nonlinear eddy viscosity models
    1. Explicit nonlinear constitutive relation
      1. Cubic k-epsilon
      2. EARSM
    2. v2-f models
      1. \overline{\upsilon^2}-f model
      2. \zeta-f model
  3. Reynolds stress model (RSM)
Large eddy simulation (LES)
  1. Smagorinsky-Lilly model
  2. Dynamic subgrid-scale model
  3. RNG-LES model
  4. Wall-adapting local eddy-viscosity (WALE) model
  5. Kinetic energy subgrid-scale model
  6. Near-wall treatment for LES models
Detached eddy simulation (DES)
Direct numerical simulation (DNS)
Turbulence near-wall modeling
Turbulence free-stream boundary conditions
  1. Turbulence intensity
  2. Turbulence length scale

Introduction

The K-epsilon model is one of the most common turbulence models. It is a two equation model, that means, it includes two extra transport equations to represent the turbulent properties of the flow. This allows a two equation model to account for history effects like convection and diffusion of turbulent energy.

The first transported variable is turbulent kinetic energy, k. The second transported variable in this case is the turbulent dissipation, \epsilon. It is the variable that determines the scale of the turbulence, whereas the first variable, k, determines the energy in the turbulence.

To define calculate boundary calculations for this model Turbulence free-stream boundary conditions

Usual K-epsilon models

  1. Standard k-epsilon model
  2. Realisable k-epsilon model
  3. RNG k-epsilon model

Miscellaneous

  1. Near-wall treatment for k-epsilon models


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