![]() 49, The College of Aeronautics, Cranfield, England, December, 1951. K.: An Investigation of Boundary Layer Effects on Two Dimensional Supersonic Aerofoils, Report No. III, Fifth Edition, Gauthier-Villars, Paris, France (1942), pp. Goursat, E.: «Cours d’Analyse Mathématique», Vol. 73, The College of Aeronautics, Cranfield, England, April, 1953.įubini, G.: Studi Asintotici per Alcune Equazioni Differenziali, Rendiconti della Reale Accademia Nazionale dei Lincei, Classe di Scienze Fisiche, Matematiche, e Naturali, 26, 253–259 (1937), No. D.: The Calculation of the Profile Drag of Aerofoils and Bodies of Revolution at Supersonic Speeds, Report No. XV, Nationaal Luchtvaartlaboratorium, Amsterdam, 1949. Timman, R.: A One Parameter Method for the Calculation of Laminar Boundary Layers, Report No. Stewartson, K.: On the Interaction Between Shock Waves and Boundary Layers, Proceedings of the Cambridge Philosophical Society, 47, 545–553, (1951). As the pitching angle increases, transition of the boundary layer at the trailing edge occurs at a higher incidence compared with the static cases. By so separating from the solid wall contour, the fluid flowing in the detached boundary layer acquires sufficient kinetic energy to overcome the remaining pressure differential produced by the shock in the potential-governed streamlined flow of the external stream. A vortex street is observed as the airfoil achieves certain pitching angles, leading to the largest boundary layer displacement thickness at the corresponding side. Even though this increment is small of itself when the flow is laminar, nevertheless the rate of change of this pressure increase (grad ∆ p) is large enough to cause the boundary layer to detach itself from the surface of the airfoil. The trailing-edge shock when first formed tends to introduce a pressure increment along the subsonic part of the boundary layer so that a pressure rise ∆ p is propagated upstream. The problem to be investigated analytically in this study is not the usual determination of the moderate alteration in pressures associated with an apparent thickening of an airfoil section when enveloped by an unseparated boundary layer, but rather an examination is made of the regenerative influence exerted far upstream, at supersonic speeds, between the boundary layer formed over the aft end of an airfoil and the shockwave interference system which is set up. ![]()
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