BEGIN:VCALENDAR VERSION:2.0 PRODID:-//Talks.cam//talks.cam.ac.uk// X-WR-CALNAME:Talks.cam BEGIN:VEVENT SUMMARY:The Stokes-flow parachute of the dandelion fruit - Cathal Cummins (University of Edinburgh) DTSTART:20170918T131000Z DTEND:20170918T133000Z UID:TALK79701@talks.cam.ac.uk CONTACT:INI IT DESCRIPTION: Cathal Cummins1\, 2\, 3 \,a)
Ignaz io Maria Viola1\, b)
Maddy Seale2\,3\,4
Daniele Certini1
Alice Macente2
Enrico Mastropaolo4
Naomi Nakayama2\, 3\, 5\, c)

1)
Institute for Energy Systems
School of En gineering
University of Edinburgh\, EH9 3DW

2)
Insti tute of Molecular Plant Sciences
School of Biological Sciences
U niversity of Edinburgh\, EH9 3BF

3)
SynthSys Centre for S ystems and Synthetic Biology
School of Biological Sciences
Unive rsity of Edinburgh\, EH9 3BF

4)
Institute for Integrated Micro and Nano Systems
Scottish Microelectronics Centre
School o f Engineering
University of Edinburgh\, EH9 3FF

5)
C entre for Science at Extreme Conditions
School of Biological Sciences
University of Edinburgh\, EH9 3BF



a) El ectronic mail: Cathal.Cummins@ed.ac.uk
b) Electronic mail: I.M.Viola@e d.ac.uk
c)Electronic mail: Naomi.Nakayama@ed.ac.uk

The fluid mechanical principles that allow a passenger jet to lift off the ground are not applicable to the flight of small plant fruit (the se ed-bearing structure in flowering plants). The reason for this is scalin g: human flight requires very large Reynolds numbers\, while plant fruit have comparatively small Reynolds numbers. At this small scale\, there are a variety of modes of flight available to fruit: from parachuting to gliding and autorotation. In this talk\, I will focus on the aerodynami cs of small plumed fruit (dandelions) that utilise the parachuting mode of flight. If a parachute-type fruit is picked up by the breeze\, it can be carried over formidable distances.

Incredibly\, th ese parachutes are mostly empty space\, yet they are effectively impervi ous to the airflow as they descend. In addition\, the fruit can become m ore or less streamlined depending on the environmental conditions. In th is talk\, I will present results from our numerical and physical modelli ng that demonstrate how these parachutes achieve such impermeability des pite their high porosity. We explore the form and function of the filame ntous building blocks of this parachute\, which confer the fruit'\;s incredible flight capacity. \; LOCATION:Seminar Room 1\, Newton Institute END:VEVENT END:VCALENDAR