Prandtl's one-equation model
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+ | {{Turbulence modeling}} | ||
==Kinematic Eddy Viscosity== | ==Kinematic Eddy Viscosity== | ||
:<math> | :<math> | ||
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</math> <br> | </math> <br> | ||
:<math> | :<math> | ||
- | C_D = 0. | + | C_D = 0.08 |
- | </math> <br> | + | </math> <ref>The exact constant used by Prandtl is currently unknown by the author. Wilcox mentions that other researchers (Emmons 1954 and Glushko 1965) have used a value ranging from 0.07 to 0.09. Prandtl's one equation model can be written in a slightly different way with different constants. For example, CHAM lists the <math>C_D</math>constant as 0.1643, but also uses another definition of the length scale and other constants (see [http://www.simuserve.com/phoenics/d_polis/d_lecs/pnalecs/lec7-22.htm#7 here]).</ref> |
+ | <br> | ||
:<math> | :<math> | ||
\sigma _k = 1 | \sigma _k = 1 | ||
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\tau _{ij} = 2\nu _T S_{ij} - {2 \over 3}k\delta _{ij} | \tau _{ij} = 2\nu _T S_{ij} - {2 \over 3}k\delta _{ij} | ||
</math> | </math> | ||
+ | |||
+ | :<math>l</math> is the turbulent length scale | ||
== References == | == References == | ||
- | + | *{{reference-book|author=Wilcox, D.C. |year=2004|title=Turbulence Modeling for CFD|rest=ISBN 1-928729-10-X, 2nd Ed., DCW Industries, Inc.}} | |
+ | *{{reference-paper|author=Emmons, H. W.|year=1954|title=Shear flow turbulence|rest=Proceedings of the 2nd U.S. Congress of Applied Mechanics, ASME}} | ||
+ | *{{reference-paper|author=Glushko, G.|year=1965|title=Turbulent boundary layer on a flat plate in an incompressible fluid|rest=Izvestia Akademiya Nauk SSSR, Mekh, No 4, P 13}} | ||
+ | |||
+ | ==Footnotes== | ||
+ | <div class="references-small"> | ||
+ | <references/> | ||
+ | </div> | ||
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Latest revision as of 19:43, 22 September 2010
Contents |
Kinematic Eddy Viscosity
Model
Closure Coefficients and Auxilary Relations
where
- is the turbulent length scale
References
- Wilcox, D.C. (2004), Turbulence Modeling for CFD, ISBN 1-928729-10-X, 2nd Ed., DCW Industries, Inc..
- Emmons, H. W. (1954), "Shear flow turbulence", Proceedings of the 2nd U.S. Congress of Applied Mechanics, ASME.
- Glushko, G. (1965), "Turbulent boundary layer on a flat plate in an incompressible fluid", Izvestia Akademiya Nauk SSSR, Mekh, No 4, P 13.
Footnotes
- ↑ The exact constant used by Prandtl is currently unknown by the author. Wilcox mentions that other researchers (Emmons 1954 and Glushko 1965) have used a value ranging from 0.07 to 0.09. Prandtl's one equation model can be written in a slightly different way with different constants. For example, CHAM lists the constant as 0.1643, but also uses another definition of the length scale and other constants (see here).
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