[nw_ds]

I am trying turbulent flow over a NACA 0012 airfoil at 5 deg angle of attack using finite difference methods with a c-grid body fitted coordinates.
The cell aspect ratio in the wake is about 1 million and I am having problems handling the properties on the coordinate cut.
Simple average have caused the convergence to be so very very slow ( practically stalled) .

I use an ADI iterative solver for solving the vorticity stream-function equations with SA turbulence model.

I even tried solving simple stream function poisson equation and the convergene is practically stalling.
I noticed that highest residual exist over the first layer ahead of the coord cut so the problem is probably caused by the updating method of the value on the cut
Am I doing something wrong ???????
I don't know what to do. Please help:confused