Static Pressure across Boundary Layer

Ilka Rudolph

I am trying to simulate the flow across a flate plate with a block profile as inlet bc, which of course converges rather fast. However, the static pressure varies across the boundary layer. This problem arises in the first cell of the domain and, moving downstream, becomes smaller due to diffusion. I tried a lot of different boundary conditions but so far nothing worked. Is this phenomenon known, or does anyone have an idea of how to get rid of that problem?