Reconfigurable origami-inspired window for tunable noise reduction and air ventilation

Conventional windows encounter significant challenges in simultaneously achieving noise reduction and ventilation. Recent advent in origami technology offers new possibilities and smart solutions to solve this bot-tlenecking problem. In this paper, we propose a novel modular-origami-based reconfigurable silencing window that achieves balanced noise mitigation and air ventilation while ensuring flexible tunability. Specifically, the balance between the two competing functions originates from the unique 'tile-void' structure of the modular origami, and the tunability is a result of the single-degree-of-freedom folding mechanism. Based on a compre-hensive understanding of the correlations between the design variables (including origami geometry, internal partition forms, and folding angles) and the acoustic characteristics of the window, on-demand sound attenua-tion for a specific target frequency band can be achieved via optimization. Broadband noise reduction can be obtained through cascading multiple origami layers, whose design can be conceived by an intuitive spectral superposition principle. Finally, we demonstrate through numerical simulations that for different working sce-narios, balanced sound attenuation and air ventilation can be achieved by simply folding the origami window. This conceptual design, alongside the reported findings, provides new ideas for the design of modular acoustic devices and contributes to addressing the noise reduction and ventilation needs for urban buildings as well as industrial installations.