Flexible aerodynamic surfaces have been shown to favorably influence flight characteristics by increasing lift, angle of attack at stall, and resistance to perturbation. The objective of the research presented within this thesis is to investigate the influence of two aspects of flight observed in biological flyers, a suction-surface flap and dynamic stall, when applied to pliant wings. A rigid ...

Optimizing the NACA0015 airfoil which is widely applied in small-scale vertical axis wind turbine to make it has a better aerodynamic performance. In the optimization process, using CST parameterization method to perturb the airfoil geometry, the thickness and camber of the airfoil are selected as the constraint, and the value of the maximum tangential force coefficient is chosen as the objecti...

The growing interest in micro aerial vehicles has brought attention to the need for an improved understanding of the aerodynamics of low-aspect-ratio wings at lowReynolds numbers. In this study, flat plate wings with rectangular and tapered planforms were fabricated with aspect ratios of 0.75, 1, 1.5, and 3, and the aerodynamic loading was measured at Reynolds numbers between 5 10 and 1 10. Sur...

Adaptive closed-loop control is used to optimize the lift-to-drag ratio of post-stall separated flow over a NACA 0025 airfoil using multiple amplitudemodulated (AM) or burst-modulated (BM), zero-net-mass-flux (ZNMF) actuators that cover the central 33% span of the airfoil. A simplex optimization approach uses the lift and drag measured by a strain-gauge balance for feedback and searches for the...

In order to develop and demonstrate a systematic approach to assessing and modeling dynamic characteristics for advanced configurations, a comprehensive dynamic wind tunnel test program was conducted for the F-16 and the F-22 at the 12-ft Vertical Wind Tunnel at WPAFB. Using the recently-developed Multi-Axis Test rig, body-axis forced oscillation, velocityvector steady rotation, and the new com...

The alula is a small structure located at the joint between the hand-wing and arm-wing of birds and is known to be used in slow flight with high angles of attack such as landing. It is assumed to function similarly to a leading-edge slat that increases lift and delays stall. However, in spite of its universal presence in flying birds and the wide acceptance of stall delay as its main function, ...

We analyze the modifications of the flow around a NACA 0015 airfoil when the flow is perturbed with an electrohydrodynamic (EHD) actuator. The device used consists of two bare electrodes flush mounted on the surface of the model operated in a discharge regime characterized by the formation of a plasma sheet contouring the body in the interelectrode space. In this study, we analyze the influence...

The paper presents a multi-body analysis of the 1/5 scale wind tunnel model of the V{22 tiltrotor, the Wing and Rotor Aeroelastic Testing System (WRATS), currently tested at NASA Langley Research Center. An original multibody formulation has been developed at the Dipartimento di Ingegneria Aerospaziale of the Politecnico di Milano, Italy. It is based on the direct writing of the equilibrium equ...

A low-order method is presented for aerodynamic prediction of wings operating at near-stall and post-stall flight conditions. The intended use in design, modeling, simulation. In this method, the flow separation due to stall modeled a vortex lattice framework as an effective reduction camber, or “decambering.” For each section wing, parabolic decambering flap, hinged location section, calculate...