Image of the Day: Sea Swirl
Image of the Day: Sea Swirl

Image of the Day: Sea Swirl

Manta rays have a unique filtration system that inspires the development of novel water filtering technology.

Sukanya Charuchandra
Sep 27, 2018

ABOVE: The gill rakers within a manta ray’s (Manta birostris) mouth help in filtration.

Researchers looked to the filter-feeding framework of the giant oceanic manta ray (Manta birostris) to create a new type of water filtration system. When the creature opens its mouth, sea water carries in minuscule food particles that that manage to not get trapped in the gills. This prevents clogging, a problem faced by most modern filters used for industrial applications such as wastewater purification. 

Using physical modeling and computational fluid dynamics, the group created a 3-D printed version of the filter-feeding apparatus. On testing this model, they found that water flow patterns between filters that resemble those within manta rays’ gills, called rakers, create small whirlpools that ricochet particulates off the filter. These findings were published September 26 in Science Advances

Fluid flows over a manta ray–inspired filter, creating vortices that would ricochet any particulate matter away from the filter while allowing water to pass through. 

R.V. Divi et al., “Manta rays feed using ricochet separation, a novel nonclogging filtration mechanism,” Science Advances, doi:10.1126/sciadv.aat9533, 2018.