Madsen Pirie

This could solve many problems. On hot nights you want the windows open to let the air in, but then you also let in those annoying noises that prevent you dropping off or which disturb your sleep. Two Korean technologists are reported to have come up with a solution. Sang-Hoon Kima at the Mokpo National Maritime University in South Korea and Seong-Hyun Lee at the Korea Institute of Machinery and Materials have developed a window that lets in one without the other. They’ve designed a sound resonance chamber using two parallel plates of transparent acrylic plastic about 150 millimetres square and separated by 40 millimetres, rather like double glazing. Kima and Lee drilled holes in the acrylic causing any sound that hits the chamber to diffract strongly into it.

They use their blocks, about the size of a paperback book, to create larger windows and report sound levels down by 20-35% over the range from 700 Hz to 2,200 Hz. The great thing is that the holes in their windows allow the air to flow through them, even while diminishing the sound. And they can tune the windows by varying the size of the holes so that some specific sounds can be screen out. They hope it will also work under water to tune out sounds that might harm marine animals.

Filed under: Updates |