In the Namib Desert, it is one of the driest places in the world. In the desert, a tiny beetle climbs up the sand dunes, tilts its body to the wind, and captures its only available water source through fog droplets.
"Water shortage is a serious problem facing global communities," said Dr. Aida shahrokian, a candidate for Akron University. "If fog droplets can be successfully captured, another source of fresh water can be provided in these areas."
Shahrokian studies how Namib Desert beetles capture enough fog to survive. She and her collaborators demonstrated aerosol filters for fog capture at the 74th Annual Meeting of APS hydrodynamic department.
Capturing fog has a lot in common with stopping droplets carrying viruses. "Over the past year, the spread of coronavirus in the air has made the public aware of the less intuitive physics of aerosols," shahrokhian said.
Based on a previous study, the researchers investigated the flow and hydrodynamic characteristics that allowed desert beetles to collect so much water. Beetles used to rely on fog dripping from vegetation, and millions of years of evolution adjusted their bodies to capture and filter fog by themselves.
On the other hand, masks use fibers to capture aerosols. A team of unrelated French scientists spent years in-depth understanding how textiles capture droplets and how these principles can design better complex filters.
"We are all familiar with using textiles to collect aerosols because we use fiber masks to stop droplets. We emit a breath or speak. This principle also applies to many other situations, including fresh collected water from fog, but many basic problems still exist," said Camille Duprat, a scientist at ladhyx and É Cole Polytechnique.
Duprat and her team tested a model system for aerosol capture in the laboratory. Then they installed a large textile fog collector under working weather conditions.
Based on these results, the researchers proposed an innovative new fog filter design, which uses structured nylon mesh to capture as much fog as possible. They say efficient design should work in more complex environments.