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.

HELIPLAT: Design, aerodynamic, structural analysis of long-endurance solar-powered stratospheric platform

Abstract: This paper presents the design and manufacture of the first European Very Long-Endurance Stratospheric Unmanned Air Vehicle, HeliPlat® (HELIos PLATform). This vehicle is a monoplane with eight brushless motors, a twin-boom tail type and two rudders. A computer program has been developed to carry out the platform design. To minimize airframe weight, high modulus carbon fibre composite material has been used extensively. Airfoil coordinates and wing planform have been optimized in order to achieve the best possible aerodynamic efficiency by using integral panel/boundary-layer methods and also to obtain the minimum possible induced drag with respect to local Reynolds airfoil. To this effect, several wind-tunnel tests were carried out so as to compare the analytically predicted airfoil performances. After an initial configuration had been worked out, a scale technological demonstrator (wing span 24 m) was designed, manufactured, and tested under shear, bending, and torsion loads. Finite element analysis was also carried out in order to predict the static and dynamic behaviour of both the full-size and scale model versions of the HeliPlat structure. The preliminary static test resulted in a high correspondence.

Poly-component blade for a gas turbine

Abstract: A lightweight, impact-resistant gas turbine blade, such as an aircraft engine fan blade, has an airfoil portion (14). The airfoil portion includes a metallic section (28) consisting essentially of metal and at least one panel section (38) not consisting essentially of metal. The metallic section extends from generally the blade root to generally the blade tip. Each panel section is an elastomeric section. Preferably, the metallic section and the at-least-one panel section only together define a generally airfoil shape.

Autonomous Sensing and Control of Wing Stall Using a Smart Plasma Slat

Abstract: DOI: 10.2514/1.24057 The concept of a self-governing smart plasma slat for active sense and control of flow separation and incipient wing stall is presented. The smart plasma slat design involves the use of an aerodynamic plasma actuator on the leading edge of a two-dimensional NACA 0015 airfoil in a manner that mimics the effect of a movable leading-edge slat of a conventional high-lift system. The self-governing system uses a single high-bandwidth pressure sensor and a feedback controller to operate the actuator in an autonomous mode with a primary function to sense and control incipient flow separation at the wing leading edge and to delay incipient stall. Two feedback control techniques are investigated. Wind tunnel experiments demonstrate that the aerodynamic effects of a smart actuator are consistent with the previously tested open-loop actuator, in that stall hysteresis is eliminated, stall angle is delayed by 7 deg, and a significant improvement in the lift-to-drag ratio is achieved over a wide range of angles of attack. These feedback control approaches provide a means to further reduce power requirements for an unsteady plasma actuator for practical air vehicle applications. The smart plasma slat concept is well suited for the design of low-drag, quiet, highlift systems for fixed-wing aircraft and rotorcraft.