报告题目：Noise reduction enabling natural ventilation technologies
报 告 人：杜良芬（香港理工大学副教授）
主 持 人：谢菠荪 教授
报告时间：2025年4月28日（星期一） 9:30—11:00
报告地点：物理与光电学院18号楼213学术报告厅
主办单位：物理与光电学院
报告人简介：
Dr. Liangfen DU joined the Department of Building Environment and Energy Engineering of the Hong Kong Polytechnic University as an Assistant Professor in April 2024. She obtained her BEng and MSc degrees in Environmental Engineering and Acoustics from Northwestern Polytechnical University in China in 2010 and 2013, respectively. She earned her second Master’s degree and a Doctorate in Acoustics from the Institut National des Sciences Appliquées de Lyon (INSA Lyon) in France in 2012 and 2016, respectively. Following her postgraduate studies, she joined JD Acoustic Pte Ltd in Singapore as an Acoustic Consultant, responsible for various industrial projects involving noise impact assessment, acoustic design, building acoustics and more. After gaining valuable industrial experience during her year at JD Acoustic, she returned to academia, working as a research fellow at the College of Design and Engineering at the National University of Singapore (NUS) from 2017 to 2021. From 2021 to 2024, She continued her research fellowship at the School of Mechanical and Aerospace Engineering at the Nanyang Technological University (NTU) in Singapore. Dr. Du’s research interests encompass noise reduction enabling natural ventilation technologies, acoustic metasurfaces, sound prediction, and environmental noise control.
报告摘要：
The rapid pace of urbanization and the steady growth of population have intensified the issue of traffic noise, particularly in densely populated cities such as Hong Kong, Singapore, and Guangzhou. For residents grappling with disruptive effects of traffic noise, the immediate solution often involves closing windows or doors that face busy roads. However, this remedy simultaneously obstructs natural ventilation. In the post-COVID-19 era, there is a growing recognition of the profound significance of natural ventilation, as it offers a multitude of advantages, including the improvement of indoor air quality, the mitigation of health-related risks, and the advancement of sustainable green building practices. In an effort to address the dual challenge of noise reduction and natural ventilation, we have introduced three innovative technologies that enable both: acoustic friendly ventilation window (AFVW), ventilated acoustic meta-barrier (VAMB) and ultracompact double layered acoustic grating (UDLAG). 1) The AFVW consists of a double layer of glass panes with two staggered openings and a mechanical ventilation system integrated between the two glass panes. Two prototype windows have been installed in the NUS (National University of Singapore) – CDL (City Developments Limited) smart green home and CDL’s premises for test-bedding and system refinements. Field measurement results have demonstrated that the AFVW achieves a noise reduction level 13dB higher than that of a conventional window with the same opening size, all while providing approximately five times the air changes per hour compared to the conventional window. 2) The VAMB is comprised of layered Helmholtz Resonators (HRs) integrated with a ventilation duct. Thanks to local resonance, this design delivers extraordinary noise reduction performance across a broad frequency band, covering the various resonant frequencies of the HRs. 3) The UDLAG consists of a double layer of rigid panels with multiple perforated slits. Different from its noise-mitigating counterparts, the UDLAG is specifically designed to deflect noise away from sensitive areas. By optimizing the positions of the slits on both layers, it can effectively concentrate the energy of an incident acoustic wave within a predefined focusing region in an arbitrary direction. This presentation will provide an in-depth discussion on these three innovative technologies, spanning from the initial prototype design and fabrication stages to comprehensive evaluations of their noise reduction and natural ventilation capabilities.
