In an air mixing arrangement wherein a primary fluid is introduced through an opening in a wall to be mixed with a secondary fluid flowing along the wall surface, the opening is airfoil shaped with its leading edge being orientated at an attack angle with respect to the secondary fluid flow stream to enhance penetration and dispersion of the primary fluid stream into the secondary fluid stream. The airfoil shaped opening is selectively positioned such that its angle of attack provides the desired lift to optimize the mixing of the two streams for the particular application. Embodiments of the arrangement can comprise a collar around the openings, multiple openings that comprise a larger opening and a smaller opening positioned downstream, pairs of openings and associated collars symmetric relationship, and nozzles on the inner side of the wall.