Abstract Ventilation window is one of the critical elements in sustainable building development, although frequently, outdoor factors such as environmental noise can limit their use. It is necessary to develop windows with both natural ventilation and noise mitigation functions. Acoustic Metamaterials (AMMs) set a new trend in solving physical challenges related to sound wave control, which can find their applications in ventilation window. This study presents a design based on acoustic metacage concept to enhance the window’s natural ventilation and acoustic performance. Finite Element Method (FEM) is used to study and optimise the acoustic performance of the metacage window. The ventilation is evaluated at the same time following predefined guidelines related to the window’s opening ratio and air-flow directivity. The metacage window structure finally, reduces the noise transmission with a mean value of 30 dB within a frequency range of 350–5000 Hz and has an opening ratio of the 33% compared to the whole system surface. The front panel gives a mean high frequencies TL contribution of 17 dB (2000–5000 Hz). Additional lateral constraint and cavities increase the TL performance up to 70% on a wider lower frequency range (350–5000 Hz). Thanks to the cavities, the resonant unit cells among the acoustic metasurface (AMS) significantly suppress sound from exiting the structure in broadband frequencies and allow bigger opening on the lateral side. This significantly contributes to the natural ventilation potential of the metacage window, which in the long term, becomes equally effective to the conventional open windows.

中文翻译：

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用于窗户系统中的噪声控制和自然通风的元笼的开发

摘要 通风窗是可持续建筑发展的关键要素之一，尽管环境噪声等室外因素经常会限制其使用。有必要开发具有自然通风和降噪功能的窗户。声学超材料 (AMM) 在解决与声波控制相关的物理挑战方面开创了新趋势，可以在通风窗中找到它们的应用。本研究提出了一种基于声学元笼概念的设计，以增强窗户的自然通风和声学性能。有限元方法 (FEM) 用于研究和优化超笼窗的声学性能。同时按照与窗户开度比和气流方向性相关的预定义准则评估通风。最后，metacage 窗口结构在 350-5000 Hz 的频率范围内以 30 dB 的平均值降低了噪声传输，并且与整个系统表面相比具有 33% 的开口率。前面板提供 17 dB (2000–5000 Hz) 的平均高频 TL 贡献。额外的横向约束和空腔在更宽的低频范围 (350–5000 Hz) 上将 TL 性能提高了 70%。由于空腔，声学超表面 (AMS) 中的谐振单元显着抑制了声音以宽带频率离开结构，并在侧面允许更大的开口。这极大地促进了元笼窗的自然通风潜力，从长远来看，它与传统的敞开式窗户同样有效。在 350-5000 Hz 的频率范围内以 30 dB 的平均值降低噪声传输，并且与整个系统表面相比具有 33% 的开口率。前面板提供 17 dB (2000–5000 Hz) 的平均高频 TL 贡献。额外的横向约束和空腔在更宽的低频范围 (350–5000 Hz) 上将 TL 性能提高了 70%。由于空腔，声学超表面 (AMS) 中的谐振单元显着抑制了声音以宽带频率离开结构，并在侧面允许更大的开口。这极大地促进了元笼窗的自然通风潜力，从长远来看，它与传统的敞开式窗户同样有效。在 350-5000 Hz 的频率范围内以 30 dB 的平均值降低噪声传输，并且与整个系统表面相比具有 33% 的开口率。前面板提供 17 dB (2000–5000 Hz) 的平均高频 TL 贡献。额外的横向约束和空腔在更宽的低频范围 (350–5000 Hz) 上将 TL 性能提高了 70%。由于空腔，声学超表面 (AMS) 中的谐振单元显着抑制了声音以宽带频率离开结构，并在侧面允许更大的开口。这极大地促进了元笼窗的自然通风潜力，从长远来看，它与传统的敞开式窗户同样有效。