A three-dimensional simulation of hovering flapping wings was performed using an immersed boundary method. This was done to investigate the effects of chordwise wing deformation on three important unsteady aerodynamic mechanisms found in flapping flight, namely Leading Edge Vortex (LEV) shedding, wake capture and clap and fling. A wing was modeled as a flat plate, flapping close to a symmetry p...

Spontaneous bilateral mode II shear ruptures were nucleated on faults in photoelastic Homalite plates loaded in uniaxial compression. Rupture velocities were measured and the interaction between the rupture front and short fault branches was observed using high-speed digital photography. Fault branches were formed by machining slits of varying lengths that intersected the fault plane over a ran...

An investigation was conducted to evaluate the effectiveness of a passive gust alleviation device (PGAD) installed in flying-wing aircraft 62.3 m wing span at large swept back angle. It performed by numerical analysis and validated wind-tunnel test 1:25 reduced scale physical model dynamic similarity full-scale aircraft. The 1- cosine with range parameters specified airworthiness regulation CS-...

The aim of this paper is to present a flutter analysis 3D Box-Wing Aircraft (BWA) configuration. box wing structure considered as consisting two wings (front and rear wings) connected with winglet. Plunge pitch motions are for each the winglet modeled by longitudinal spring. In order exert effect wing-joint interactions (bending torsion coupling), ends spring located on gravity centers tip sect...

With millions of years evolution, owls have developed many excellent characteristics in terms their flight. The speed an owl flight is similar to the relative blade a small wind turbine with respect air. Therefore, wing airfoil selected as design reduce flow separation under low Reynolds number. In this study, we analyze wing-section and non-smooth leading-edge shape owl's wing, implement ortho...

The vortical structures over a thin rectangular wing with very low aspect ratio of 0.277 were investigated in wind tunnel at an effective Reynolds number $3 \times 10^6$ . When applying pitch-up motion pivoted mid-chord, the maximum lift angle was increased increase pitch rate, but coefficient reduced. pitching also caused delay development wing, which rate. leading-edge vortex due to nearly id...

Aerodynamic performance and agility during flapping flight are determined by the combination of wing shape and kinematics. The degree of morphological and kinematic optimisation is unknown and depends upon a large parameter space. Aimed at providing an accurate and computationally inexpensive modelling tool for flapping-wing aerodynamics, we propose a novel CFD (computational fluid dynamics)-in...

Past studies have shown that birds use their wings not only for flight, but also when ascending steep inclines. Uphill flap-running or wing-assisted incline running (WAIR) is used by both flight-incapable fledglings and flight-capable adults to retreat to an elevated refuge. Despite the broadly varying direction of travel during WAIR, level, and descending flight, recent studies have found that...

This paper presents transonic buffet simulations over a swept wing of supercritical airfoils with Unsteady Reynolds-Averaged Navier-Stokes (URANS) and Detached-Eddy Simulation (DES) methods. The NASA SC(2)-0714 airfoil is used as wing profile. Computations are conducted at free-stream Mach numbers from 0.72 to 0.84 for Reynolds number 45.0 × 10 based on aerodynamic chord length. Firstly, 2D NAS...