I don’t know enough about the underlying science to know how valuable this might be for people who work in the industry. But it seems like there are some fundamental scientific breakthroughs being made, and the way these might be employed by engineers is some thing I’m hoping to learn about.
Recent research into metamaterials for sound absorption -- any new products?
Wondering if anyone has heard of some new acoustic treatments for audio based on the following research (now 5 years old) into meta-materials:
https://www.sciencedaily.com/releases/2016/09/160920112321.htm
I found one brief further scientific paper, here: https://www.mwmresearchgroup.org/blog/archives/03-2020
And the application of such technology, here: https://www.sciencedirect.com/science/article/abs/pii/S0375960119303895?dgcid=rss_sd_all
"we propose an acoustic metamaterial for low-frequency (<500 Hz) absorptions, composed of three nested square split tubes with inverted opening directions. The efficiency of the absorber is investigated both numerically and experimentally, and absorptions at the peeks are found to exceed 90% and the frequency can be effectively adjusted by tuning its geometric parameters. We further test its yield strength under compression and confirm its buckling behavior happens from the outmost layer. This tunable acoustic metamaterial with a fairly good mechanical strength may lead to broad applications in noise reduction."
If these meta-materials are well-implemented into acoustic panels, building materials, etc. it seems that some real changes in room acoustic treatment might be on the horizon.
P.S. Some write about collecting energy from acoustic energy:
https://journals.sagepub.com/doi/full/10.1177/1687814017748077
"Therefore, many studies on self-powered electronic components by harvesting energy from ambient have been carried out, showing the potential benefit of eliminating the battery replacement and disposal. Acoustic energy is a clean, ubiquitous, and sustainable energy source, and it is abundant in some circumstances, thus investigating the acoustic energy reclaiming mechanisms is of significance."
https://www.sciencedaily.com/releases/2016/09/160920112321.htm
I found one brief further scientific paper, here: https://www.mwmresearchgroup.org/blog/archives/03-2020
And the application of such technology, here: https://www.sciencedirect.com/science/article/abs/pii/S0375960119303895?dgcid=rss_sd_all
"we propose an acoustic metamaterial for low-frequency (<500 Hz) absorptions, composed of three nested square split tubes with inverted opening directions. The efficiency of the absorber is investigated both numerically and experimentally, and absorptions at the peeks are found to exceed 90% and the frequency can be effectively adjusted by tuning its geometric parameters. We further test its yield strength under compression and confirm its buckling behavior happens from the outmost layer. This tunable acoustic metamaterial with a fairly good mechanical strength may lead to broad applications in noise reduction."
If these meta-materials are well-implemented into acoustic panels, building materials, etc. it seems that some real changes in room acoustic treatment might be on the horizon.
P.S. Some write about collecting energy from acoustic energy:
https://journals.sagepub.com/doi/full/10.1177/1687814017748077
"Therefore, many studies on self-powered electronic components by harvesting energy from ambient have been carried out, showing the potential benefit of eliminating the battery replacement and disposal. Acoustic energy is a clean, ubiquitous, and sustainable energy source, and it is abundant in some circumstances, thus investigating the acoustic energy reclaiming mechanisms is of significance."