Meeting Abstract

9.2  Tuesday, Jan. 4  A view of dragonfly and damselfly aerodynamics through high-speed stereo PIV HENNINGSSON, P.*; BOMPHREY, R.J.; University of Oxford; University of Oxford per.henningsson@zoo.ox.ac.uk

Current research aimed at developing Micro Air Vehicles (MAVs) has led to increasingly intricate mechanisms for driving wings through complex motions, and has also produced an array of sophisticated flight control systems. Conversely, research into selecting appropriate wing morphologies for certain performance characteristics has received comparatively less attention. Detailed knowledge explaining the diversity of insect wing shape, allied with ecological data, can help to inform MAV wing designs so long as their resulting aerodynamic performance can be ascertained. Measuring the flow around insects in free flight is a challenging problem due to their typically small size and high wingbeat frequencies. A newly-installed, high-speed (1kHz), stereo-PIV system is beginning to reveal quantitative detail about the aerodynamic mechanisms employed by British Odonata (dragonflies and damselflies). Here we present results from two types of analysis. The first uses a transverse light sheet plane to reveal time-resolved wake topologies (with a long-term view to gauge comparative aerodynamic efficiency by downwash distribution). The second uses a longitudinal light sheet plane for on-wing measurements of circulation and spanwise flow within Odonate leading-edge vortices as they form, develop and shed during voluntary bouts of flight.