The kinematics and hydrodynamics of free-swimming mayfly larvae (Chloeon dipterum) were investigated with the aid of a simple wake visualisation technique (tracer dyes) and drag measurements on dead insects. The basic swimming movement consists of a high-amplitude dorso-ventral undulation and, during continuous swimming, this produces a wake of ring vortices shed alternately to the dorsal and v...

Operating horizontal axis wind turbines (HAWT) generate large-scale wake structures that can have considerable impact on downwind turbines. A HAWT exposed to vortices from upwind turbines generally produces reduced power and experiences increased structural vibrations that cause disproportionally accelerated material fatigue. Numerical simulation of the turbulent flow field is a viable approach...

Flying insects typically possess two pairs of wings. In beetles, the front pair has evolved into short, hardened structures, the elytra, which protect the second pair of wings and the abdomen. This allows beetles to exploit habitats that would otherwise cause damage to the wings and body. Many beetles fly with the elytra extended, suggesting that they influence aerodynamic performance, but litt...

§ The interactive aerodynamics of new V/STOL designs require a new approach to ground testing, where multiple properties are measured both on and away from surfaces during continuous changes in test parameters. Using a set of experiments of increasing complexity, a new capability is demonstrated for capturing surface pressure, velocity fields and vortex flow features over a range of test parame...

An experimental study was conducted to quantify the characteristics of wake vortex and flow structures around a high-rise building model as well as the resultant wind loads (both forces and moments) acting on the test model in tornado-like winds. In addition to measuring wind loads acting on the tested high-rise building model using a highsensitivity load cell, a digital Particle Image Velocime...

Experimental measurements and analysis of the flight of bats are presented, including kinematic analysis of high-speed stereo videography of straight and turning flight, and measurements of the wake velocity field behind the bat. The kinematic data reveal that, at relatively slow flight speeds, wing motion is quite complex, including a sharp retraction of the wing during the upstroke and a broa...