Airfoil

About: Airfoil is a research topic. Over the lifetime, 24696 publications have been published within this topic receiving 337709 citations. The topic is also known as: aerofoil & wing section.

Impingement cooled airfoil with bonding foil insert

Abstract: An impinqement cooled airfoil is fabricated by diffusion bonding a pair of airfoil half-sections together using an insert which is prefabricated from diffusion bonding foil. The insert is perforated so as to act as an impingement baffle. Axially-extending ribs may be formed on the internal walls of the airfoil half-sections or on the insert to support and accurately space the insert member from the internal walls so as to optimize impingement cooling.

An Experimental Investigation of a Low-Speed Circulation-Controlled Aerofoil

Abstract: Experiments performed on a low-speed circulation-controlled aerofoil are described. The aerofoil was of elliptic section with the circulation controlled by means of a jet blowing around the blunt trailing edge. Results for the lift, drag and pitching moment on the aerofoil are presented as functions of the blowing momentum coefficient and the angle of incidence. The results are for a two-dimensional aerofoil. Possible applications of this type of aerofoil are briefly discussed.

Downwash and Wake Behind Plain and Flapped Airfoils

Abstract: Extensive experimental measurements have been made of the downwash angles and the wake characteristics behind airfoils with and without flaps and the data have been analyzed and correlated with the theory. A detailed study was made of the errors involved in applying lifting-line theory, such as the effects of a finite wing chord, the rolling-up of the trailing vortex sheet, and the wake. The downwash angles, as computed from the theoretical span load distribution by means of the Biot-Savart equation, were found to be in satisfactory agreement with the experimental results. The rolling-up of the trailing vortex sheet may be neglected, but the vertical displacement of the vortex sheet requires consideration. By the use of a theoretical treatment indicated by Prandtl, it has been possible to generalize the available experimental results so the predictions can be made of the important wake parameters in terms of the distance behind the airfoil trailing edge and the profile-drag coefficient. The method of application of the theory to design and the satisfactory agreement between predicted and experimental results when applied to an airplane are demonstrated.

Development of a linear unsteady aerodynamic analysis for finite-deflection subsonic cascades

Abstract: An unsteady potential flow analysis, which accounts for the effects of blade geometry and steady turning, was developed to predict aerodynamic forces and moments associated with free vibration or flutter phenomena in the fan, compressor, or turbine stages of modern jet engines Based on the assumption of small amplitude blade motions, the unsteady flow is governed by linear equations with variable coefficients which depend on the underlying steady low These equations were approximated using difference expressions determined from an implicit least squares development and applicable on arbitrary grids The resulting linear system of algebraic equations is block tridiagonal, which permits an efficient, direct (ie, noniterative) solution The solution procedure was extended to treat blades with rounded or blunt edges at incidence relative to the inlet flow