Scientists develop 3D-printable ‘sonic black hole’ to absorb sound

A collaborative research team from Chongqing Industry Polytechnic College, Northwestern Polytechnical University in China, and Universitat Ramon Llull in Spain has developed a device described as a ‘sonic black hole’. Published in the journal Applied Acoustics, the technology uses a 3D-printable structure designed to trap sound waves within pipes and ducts.

Unlike astronomical black holes, this device relies on geometry rather than gravity. By utilizing a progressive change in duct geometry, sound waves are slowed down and their energy is concentrated toward the end of the structure, preventing them from reflecting back as echoes.

This device is designed as a separate accessory that can be inserted into existing ventilation, air conditioning, industrial exhaust, or plumbing systems. This offers an advantage over conventional designs that require modifying the walls of the ducts or manufacturing integrated structures.