The Lily Impeller is a mixer "designed using the elegant and effective geometries found in natural fluid flow," its designer has explained. Its shape, based on the logarithmic curve (known as the Fibonacci spiral) found in nautilus shells and whirlpools, accommodates a centripetal flow of liquid with little friction. As a result, the device is capable of circulating millions of gallons of water with a minimal amount of energy. Used in municipal reservoir tanks, the mixer prevents drinking water from stagnating, reducing the need for disinfectant additives.
Gallery label from Design and the Elastic Mind, February 24–May 12, 2008.