Still Waters

Imagining a ship invisible to waves
October 1, 2011
Still Waters

Duke engineer Yaroslav Urzhumov is building a boat. At this point, it’s a theoretical boat—a postulated design, really—but it might end up revolutionizing the shipping industry. That’s because Urzhumov’s boat makes water stand still.

Urzhumov accomplishes that trick by envisioning a “cloak” made of porous materials that would cover a boat’s hull. The cloak would pump water through holes and passages at the same speed as surrounding water, preventing it from being displaced by the ship. “Ships expend a great deal of energy pushing the water around them out of the way as they move forward,” says Urzhumov. “What our cloak accomplishes is that it reduces the mass of fluid that has to be displaced to a bare minimum.” And that could mean faster, more energy-efficient ocean liners.

Urzhumov, an assistant research professor in electrical and computer engineering, works in the laboratory of David R. Smith, William Bevan Professor of electrical and computer engineering. Smith’s lab made news in 2006 by devising cloaks that make objects seem invisible to light and sound. This follows the same basic principle, using manmade materials to alter the normal forces of nature. The U.S. Office of Naval Research helped fund his work.