Hi,

has anyone tried to compare flat plate laminar solution of STAR with Blasius's formula? I seem to have a very good match for Rex = 1e5, but it deteriorate on either sides of this value... Any ideas as to why?

Blasius's formula is valid for low Re number and upto 1e5. if u have tried flat plate with very low Re then change er Turbulence model and also focus on near wall refinement.

I have tried it with Re number above AND below 1e5. The only value it works fine is at 1e5. Below this the skin friction given by star is below Blasius. I am running laminar case. The y+ values I calculated are below 1, so I assume the wall cells are refined enough.

Anyway I had tried the laminar flow on an adiabatic flat pate characterized by a free stream Mach number M = 0.3 and by a Reynolds number based on the free stream condition and the plate length Re = 500. the leading edge starts at x = 0. The result was in good agreement.

Basically the exponent in Blasius's formula implies 1/7 power law velocity profile and hence modified for surface roughness.