Linear eddy viscosity models
From CFD-Wiki
(Difference between revisions)
m |
m |
||
Line 15: | Line 15: | ||
This linear relationship is also known as ''the Boussinesq hypothesis''. For a deep discussion on this linear constitutive relationship, check section [[Introduction to turbulence/Reynolds averaged equations]]. | This linear relationship is also known as ''the Boussinesq hypothesis''. For a deep discussion on this linear constitutive relationship, check section [[Introduction to turbulence/Reynolds averaged equations]]. | ||
- | There are several subcategories for the linear eddy-viscosity models, depending on the number of (transport) equations | + | There are several subcategories for the linear eddy-viscosity models, depending on the number of (transport) equations solved for to compute the eddy viscosity coefficient. |
# [[Algebraic turbulence models|Algebraic models]] | # [[Algebraic turbulence models|Algebraic models]] |
Revision as of 22:29, 30 October 2009
These are turbulence models in which the Reynolds stresses, as obtained from a Reynolds averaging of the Navier-Stokes equations, are modelled by a linear constitutive relationship with the mean flow straining field, such as:
where is the coefficient termed turbulence "viscosity" (also called the eddy viscosity), and is the mean strain rate defined by:
This linear relationship is also known as the Boussinesq hypothesis. For a deep discussion on this linear constitutive relationship, check section Introduction to turbulence/Reynolds averaged equations.
There are several subcategories for the linear eddy-viscosity models, depending on the number of (transport) equations solved for to compute the eddy viscosity coefficient.