Boundary Condition in Gambit

Kirit

HI, I am trying to simulate a wind turbine in a tunnel 2D. I have done that good so far. the turbine had some blades . i need to measure the forces developed around those blades. But as boundary conditon i declared the blade surface as interior in GAMBIT but when i import then in fluent it shows error and convert those bundary surface as wall and my program does not converge. i have tried the same geomerty without declaring the boudary conditon of blades then it converged. i have also tried by reducing under-relaxation factor but no improvement.

So my question is what will be the boudnary conditon of the blade surface. i need to declare both surface in order to get the values.

thanks in advance

Kirit