Compute Wall Spacing for a Given Y+

These computations are based on flat-plate boundary layer theory from Frank M. White's Fluid Mechanics 5th edition, page 467.

The Math*

${Re}_{x} = \frac{ρ U_{∞} L}{μ}$

$C_{f} = \frac{0.026}{{Re}_{x}^{1 / 7}}$

$τ_{wall} = \frac{C_{f} ρ {U_{\infty}}^{2}}{2}$

$U_{fric} = \sqrt{\frac{τ_{wall}}{ρ}}$

$Δ s = \frac{y^{+} μ}{U_{fric} ρ}$

*Note: The equations are done using MathML. Certain browsers (Chrome, for example), currently do not properly render MathML.

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