On the passive laminar flow control technique of swept wing

The key of swept wing passive laminar flow control based on leading-edge roughness elements array technique is the choice of control wavelength. The author advanced the quickest wave theory from the view of the physical mechanism of control wave and flow interaction. The author investigated infinite swept wing optimal control wavelength through solving three-dimension incompressible Orr-Sommerfeld equation by using Mack method. Numerical results validated 8 mm is the control wavelength under Saric's experimental condition by fixed wavelength method. By using adaptive searching method the optimal control wavelengths of this model under different conditions. Transition delaying was achieved through wind tunnel experiments. This paper also advanced the technique of roughness elements array appended by silk-screen, and mixed solvent sublimation method, which enriched the experimental means.