[hxaxtma]

Hi guys,

i really need help calculating the wall shear stress component on a cylinder.
x=y=1 m diameter
z=height

First I transformed coordinates in cylindrical ones with
{R}=SQRT({X}*{X}+{Y}*{Y})
{Theta}=ATAN2({Y},1*{X})

Now my normal component to surface is
{dn}={R}*cos{Theta}
Tangential Component:
dt=dn={R}*sin{Theta}

For tau_w I defined:
{dU}=SQRT({dUdX}**2+{dUdY**2})
{tau_w}={mu}*{dU}/{dn}

If I compare the results to openFoam i got different numbers, what am I doing wrong?