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Mechanical and Civil Engineering Seminar

Thursday, November 14, 2019
11:00am to 12:00pm
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Gates-Thomas 135
Elephant Olfaction and a Wombat's Cubic Feces
David Hu, Associate Professor, School of Mechanical Engineering, Georgia Institute of Technology,

Elephants eat 200 kg of food per day, equating to 200 grams every minute. To locate food quickly, they have more olfactory genes than any other animal, and they also employ periodic sniffs with their trunk. In this talk, I'll show how the frequency of sniffing changes with body size. We will apply the fluid mechanics of cardiovascular flows to calculate the time for odors to diffuse to the sensor. We visualize flows using experiments with GROMIT, a bellows-driven device that inhales air at the sniffing frequencies of animals, and was awarded third place in a cheese-sniffing machine olfaction competition in Montreal. Lastly, we will present our experiments and modeling of a wombat's cubic feces. The flat faces are created through a drying process analogous to the formation of columnar joints in Giant's Causeway, Ireland; the corners are sculpted by non-uniform material properties in the intestinal wall. Audiences will learn how to use engineering principles to study natural phenomena.

For more information, please contact Carolina Oseguera by phone at (626) 395-4271 or by email at