“The thorny devil, a tiny highly specialised lizard from the central Australian desert which lives entirely on ants has each scale enlarged and drawn out to a point in the centre. Few birds could relish such a thorny mouthful and to that extent, they must be a very effective defence, but the shape of the scales also serves another and most unusual function. Each is scored with very thin grooves radiating from the central peak. During cold nights, dew condenses on them and is drawn by capillary action along the grooves and eventually down to the tiny creature’s mouth.” (Attenborough 1979:164)
The Thorny Devil (Moloch horridus) can gather all the water it needs directly from rain, standing water, or from soil moisture, against gravity without using energy or a pumping device. Water is conveyed to this desert lizard’s mouth by capillary action through a circulatory system on the surface of its skin, comprised of semi-enclosed channels 5-150 µm wide running between cutaneous scales. Channel surfaces are heavily convoluted, greatly increasing the effective surface area to which water can hydrogen-bond and hence capillary action force. Passive collection and distribution systems of naturally distilled water could help provide clean water supplies to the 1 billion people estimated to lack this vital resource, reduce the energy consumption required in collecting and transporting water by pump action (e.g., to the tops of buildings), and provide a variety of other inexpensive technological solutions such as managing heat through evaporative cooling systems, protecting structures from fire through on-demand water barriers, etc.
Inspired by how whirlpools and hurricanes works in nature, inventor Jay Harmon uses the spiral shape to stir 10 million gallons of water with a couple of light bulbs worth of power, keeping in this way hundreds of water storage tanks clean without the use of chlorine or other chemicals.
Researchers Look to Convert Tidal Energy Into Electricity with Whale-Inspired Ocean Turbine Blades
Now lessons learned from the ocean’s largest mammals has inspired United States Naval Academy researchers to tackle one of the serious challenges of this technology: the low velocity associated with many tidal flows and the difficulty of extracting useful energy from low speed flows using current designs. They are presenting their findings at the American Physical Society’s Division of Fluid Dynamics (DFD) meeting in Long Beach, CA.
“We designed a novel blade modification for potential turbine performance improvement, which was inspired by humpback whale flippers, with the addition of tubercles, or bumps, to the leading edge of each blade,” explains Mark Murray, a Naval Academy engineering professor. Previous research demonstrated the addition of biomimetically derived protuberances (technology that mimics nature) improved stall characteristics and aerodynamic performance.”
The researchers’ modified blades proved to be more effective in extracting energy at low speeds. Importantly, the blades did not degrade performance at high flow speeds or increase the mechanical complexity of the turbine.
Applications of this research may include the development of turbine designs that are more effective in converting low velocity tidal flow energy into useful electricity and more economically feasible to deploy.
This project was conducted as an undergraduate independent research study by Ensign Timothy Gruber, who is currently attending Massachusetts Institute of Technology’s masters program, with Murray and Associate Professor David Fredriksson in the Naval Architecture and Ocean Engineering Department acting as his faculty advisors.
Found on ScienceDaily
Efficient Ocean Turbines inspired by Whale flippers
Biomimicry has given us everything from electronics displays to Velcro. Now we can thank nature for weaning us off unsustainable energy sources. Researchers from the United States Naval Academy have figured out that whale flippers can solve one of the most vexing problems associated with underwater tidal flow turbines.
Underwater turbines convert energy from the ocean’s tidal flow into electricity, but researchers in the past have had trouble grabbing useful energy from low-speed tidal flows. By adding humpback whale flipper-inspired tubercles (bumps) to the leading edge of each turbine blade, Naval Academy researchers found that they were able to extract more energy from low-speed waves—without hurting performance when waves rushed in at high speeds.
According to Science Daily, the research could lead to new underwater turbine designs. We’ll be watching WhalePower, a startup that designs tubercle-inspired wind turbines (pictured above). The company’s whale-based designs can already be seen in the Tubercle Technology HVLS (High Volume Low Speed) fan, a product sold in partnership with industrial and agricultural fan manufacturer EnviraNorth Systems Ltd. And that’s just the beginning. WhalePower claims that more whale-inspired fans, turbines, and rotors will all be available soon.
Found on FastCompany