# Wall shear stress

(Difference between revisions)
 Revision as of 08:22, 22 November 2011 (view source)Zonder (Talk | contribs) (add unit)← Older edit Revision as of 18:16, 23 November 2011 (view source)Peter (Talk | contribs) m (Reverted edits by Zonder (talk) to last revision by Peter)Newer edit → Line 4: Line 4: Where $\mu$ is the [[Dynamic viscosity|dynamic viscosity]], $u$ is the flow velocity parallell to the wall and $y$ is the distance to the wall. Where $\mu$ is the [[Dynamic viscosity|dynamic viscosity]], $u$ is the flow velocity parallell to the wall and $y$ is the distance to the wall. - - The SI unit of the kinematic viscosity is $Pa$ or $\frac{kg}{m\cdot s^2}$.

## Revision as of 18:16, 23 November 2011

The wall shear stress, $\tau_w$, is given by:

$\tau_w = \mu \left(\frac{\partial u}{\partial y} \right)_{y=0}$

Where $\mu$ is the dynamic viscosity, $u$ is the flow velocity parallell to the wall and $y$ is the distance to the wall.