Law of the wall
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:<math>u^+ = \frac{1}{\kappa} \, ln(y^+) + B</math> | :<math>u^+ = \frac{1}{\kappa} \, ln(y^+) + B</math> | ||
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+ | and close to the wall in the viscous sublayer | ||
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+ | :<math>u^+ = y^+</math> | ||
Where: | Where: | ||
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|<math>\kappa</math> || von Karman's constant (<math>\approx 0.41</math>) | |<math>\kappa</math> || von Karman's constant (<math>\approx 0.41</math>) | ||
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- | |<math> | + | |<math>B</math> || Constant (<math>\approx 5.1</math>) |
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In the image y is replaced with the letter n. | In the image y is replaced with the letter n. | ||
- | [[Image: | + | [[Image:Img_lawOfTheWall_whiteBG.png]] |
{{stub}} | {{stub}} |
Latest revision as of 08:32, 7 September 2011
In the log layer the velocity profile can be estimated with the log law:
and close to the wall in the viscous sublayer
Where:
Dimensionless velocity Dimensionless wall distance von Karman's constant () Constant ()
We should have a lin-log plot here of a typical turbulent boundary layer to illustrate where the log-law is valid, anyone have one handy?
In the image y is replaced with the letter n.