Measurements of the structure and evolution of the tip vortex from a rotor in low-speed forward flight are presented. On the advancing blade spanwise flow on the pressure side of the blade is comparable in magnitude to the inflow. Core circumferential velocity profiles show multiple features during formation. Trajectories and peak core velocities of the tip-vortex during its formation on top of...

The wings of many insects accumulate considerable wear and tear during their lifespan, and this irreversible structural damage can impose significant costs on insect flight performance and survivability. Wing wear in foraging bumblebees (and likely many other species) is caused by inadvertent, repeated collisions with vegetation during flight, suggesting the possibility that insect wings may di...

In this paper the application of a wing fence on an unmanned aerial vehicle (UAV) is examined. The UAV under consideration characterized by flow separation initiating at tip, leading to lo...

The interaction between the slipstream of propellers and wing an aircraft with distributed electric propulsion (DEP) could benefit aerodynamics. A conceptual design optimization are carried out in order to increase range general aviation without affecting its takeoff landing velocity same fuselage condition. Propellers modelled using actuator disk (AD) theory, is vortex lattice method (VLM) obt...

The effect of a wind gust on the aerodynamic characteristics of a rigid wing undergoing insect-based flapping motion is studied numerically. The turbulent flow near the flapping wing is described by the 3-D unsteady compressible Reynolds-Averaged Navier-Stokes equations with the Spalart-Allmaras turbulence model. The governing equations are solved using a second-order node-centered finite volum...

The pattern of differentiated wing structures formed following 180° rotation of the undifferentiated wing bud tip on its base was examined in detail. These analyses were performed to determine the handedness and origin of the supernumerary structures which arise. In contrast to the variable classes of symmetric and/or asymmetric limb anatomies observed following the same operation with amphibia...

Recent achievements in the application of activematerials induced-strain actuation to counteract aeroelastic and vibration effects in helicopters and fixed wing aircraft are reviewed. First, the induced-strain actuation principles and capabilities are briefly presented. Next, the attention is focused on the smart rotor blade applications. Induced twist, active blade tip, and active blade flap a...

Given the growth rate throughout an embryonic rudiment, one can calculate how its parts must shift as it gets bigger, and so plot fate maps showing their future positions. The calculation is done here for the chick wing-bud from stage 18 to 25, using published data for mitotic index and cell packing density, and new measurements of size and shape. Two main findings are: (1) the wing-bud in this...