Abstract: This article presents a method to correct tunnel wall and support interferences based on vortex lattice method. The method needs to know the porosity parameter Q involved in the boundary condition of ventilated wall in the high speed wind tunnel. FL-21 wind tunnel wall characteristic curve Q-Ma is determined by combining computations with experiments. Q increases with Ma in subsonic speeds. According to the curve some test data are corrected for tunnel wall and support interferences. The corrected results agree -well with those attained from theories published abroad and from experiments obtained at home.

Key words: Slotted walls, wall interference correction, transonic wind tunnels.