Thursday, 22 June 2017

super sonic

With the very busy Schipol Airport just nine kilometres outside of Amsterdam, noise pollution has posed a serious problem for residents living in that sound footprint, which can propagate over an expanse of some thirty kilometres due to the featureless plain that surrounds the facility.
Back in 2008, however, officials seeking to remedy this situation accidentally noticed that when the fields around the airport were ploughed, noise levels dropped. Inspired and drawing on the nineteenth century experiments and demonstrations of father of acoustics, mathematician and musician Ernst Chladni, an architectural firm dug runnels and raised berms to change the soundscape of the area. The symmetrical furrows are separated by the equivalent to the wave-length of the general racket and disrupt the spread of the noise, cutting it in half. The park that separates the airport campus from populated areas has features named in Chladni’s honour—whose brilliance might be most immediately recalled with his demonstrations of sound propagating through a solid medium illustrated by the way grains of sand arrange themselves according to the vibration. Those shapes (nodal patterns) are called Chladni figures.