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Skin friction coefficient

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Revision as of 17:46, 7 April 2008 by Roycewilliam (Talk | contribs)
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The skin friction coefficient, C_f, is defined by:

C_f \equiv \frac{\tau_w}{\frac{1}{2} \, \rho \, U_\infty^2}

Where \tau_w is the local wall shear stress, \rho is the fluid density and U_\infty is the free-stream velocity (usually taken ouside of the boundary layer or at the inlet).

It is related to the momentum thickness as follows: C_f = 2(d theta)/ (d x)

An empirical relation you may use for comparison is: C_f = 0.0583/(Re )^0.2

Someone should add some correlations and references for them here

My wiki