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Theoretical Exploration of Barrel-Shaped Drops on Cactus Spines
1Department of Mechanical and Aerospace Engineering, University of Texas at Arlington 500 West First Street, Woolf Hall 226, Arlington, Texas 76019, United States.
Abstract:
To survive an arid environment, desert cacti are capable of harvesting water from fog by transporting condensed water drops using their spines. Cactus spines have a conical shape. In this work, on the basis of the difference of liquid pressure, a new theoretical model has been developed for a barrel-shaped liquid drop on a conical wire. This model is further simplified to interpret the effects of contact angles, conical angle, surface microgrooves, and gravity on the drop movement along a cactus spine.
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