If you have ever hiked in the woods and been surrounded by the sight and smell of pine trees, you may have taken a closer look at pine needles and wondered how their shape, material properties, and surface wettability are all influenced by rainfall.
In Physics of Fluids, from AIP Publishing, researchers at the University of Central Florida are currently probing how well pine needles allay the impact of rain beneath the tree. Andrew K. Dickerson and Amy P. Lebanoff explored the impact of raindrops onto fixed, noncircular fibers of Pinus palustris, aka the longleaf pine, by using high-speed videography to capture the results.
“Drops impacting fixed fibers are greatly deformed and split apart,” said Dickerson. “As expected, the breakup of the drop and the force felt by the fiber is dependent on drop size and speed.”
Impact force and the shape of the resulting lobe of water also