A parametric experimental study of the slotted-wall boundary condition

An experimental study of slotted upper and lower walls in a two dimensional transonic wind tunnel with solid sidewalls is reported. Results are presented for several slot spacings and slot openness ratios. The experimental data were pressure measurements which were made on an airfoil model and on a sidewall near one of the slotted walls. The slotted-wall boundary condition coefficient, which related the pressure and streamline curvature near the wall, was determined from the wall pressure measurements. The measured wall-induced interference was correlated with the experimental values for the boundary condition coefficient. This correlation was compared with theory.