Is noise from ABOVE turning you into a night owl?

This is Sandra Tsing Loh with the Loh Down on Science.

YAWN… Time for bed… until… SWOOOSH! Another loud airplane blows over your house! Noise pollution is more than annoying. It has negative impacts on humans AND animals. How can we cut down on all that racket? First let’s look at how it happens. Air flows across a winged structure, like the turbine blades in a jet engine. That creates turbulence…and noise!  

Enter Lei Wang and colleagues from Xi’an Jiaotong University. They looked to owls, some of the quietest fliers, for a solution! They designed turbine blades with uniform serrated edges, like an owl’s feathers! These cuts break up the incoming air, creating less powerful sound. During their initial experiments, the new design reduced noise by over 20 decibels! AND when the serrated edges weren’t uniform… the machines got EVEN quieter!

The researchers believe this could lessen the noise of planes, vehicles, and even your AC unit. I’m gonna sleep like a baby…

Reference: Wang, L., & Liu, X. (2022). Aeroacoustic investigation of asymmetric oblique trailing-edge serrations enlighted by owl wings. Physics of Fluids, 34(1), 015113.