In a new research project, engineers created a fur-like, rubbery material capable of trapping air between individual hairs when it is submerged. This is the same technique small furry mammals use to remain warm and even dry while diving, since they lack the kind of insulating blubber of walruses and whales.
“Currently wetsuits are made of heavy neoprene rubber insulation,” Alice Nasto, an MIT graduate student in Mechanical Engineering, who worked on the project, told Digital Trends. “If you use a textile that is more lightweight and can entrain air, it could allow you to be nimble, while still keeping warm. [The fur of semi-aquatic mammals] is specially adapted to trap air underwater, providing a layer of insulation. Our project aims to understand how air trapping occurs during a dive, when you’re crossing between the air above water and going below water.”
The impetus behind the work came when a group of MIT students visited Taiwan, where they visited several sporting goods makers, including Sheico Group, which produces wetsuits. Based on this initial meeting, Nasto was given the job of finding examples in nature that could be used a design model for streamlined wetsuits that would allow swimmers and divers to remain warm and dry while in the water.
“We created a simple model of fur with rubbery hairy samples, where we precisely control the spacing and length of the hairs,” she continued. “We came up with a mathematical model to predict how much air is trapped based on the spacing and length of the hairs, the viscosity of the fluid, and the speed of the dive.”
Future iterations of the project will aim to understand how air remains trapped after a dive. Should all go to plan, it may not be too long before otter-inspired wetsuits are popping up in our local sporting good stores — or elsewhere.
“There are also exciting applications in the industrial process of dip coating, where a material is plunged in a liquid and then drawn out of the liquid bath, leaving a thin film of the fluid on the material,” Nasto said. “Many materials have texture, and this work can tell you how slowly you need to plunge your textured material to avoid trapping air, which would cause uneven coating.”
