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Seminar - Exploring microperforated panel designs for duct noise control by Dr. Cheng Yang
日期:2018 年 08 月 15 日 ( 星期三)
Time:11:00 am – 12:00 pm
Venue:EF305

Abstract:

Over the years, microperforated panels (MPPs) have been used to solve a variety of acoustics problems. In all those applications, MPPs are frequently accompanied by the backing air cavity so that they constitute a resonance system which leads to an effective acoustic absorption around its resonance frequency. Subsequent research is often seen in terms of MPP parameters optimization, backing cavity design and the incorporation of active components into the absorber to enhance the absorption performance. Those efforts however remain in the framework of cavity-backed MPP absorber design. In this talk, we will explore an alternative MPP design where the MPP is used independently for acoustic absorption without the commonly used backing cavity. For this mechanism to be effective, a MPP should be placed in an environment in which an acoustic pressure difference occurs between the two sides of the MPP. Such an environment is found in a curved duct where the axial wavenumber is radius dependent. A MPP partition separating the bend into two curved subdomains is then able to realize acoustic absorption without the need for a backing cavity. This is evidenced by both simulation and experiment.

Bio-sketch:

Dr. Cheng Yang is currently a tenure-track associate professor in School of Mechanical Engineering at Shanghai Jiao Tong University. He obtained his BS in mechanical engineering from Southeast University in 2007. After that, he spent 9 years in Department of Mechanical Engineering at The Hong Kong Polytechnic University where he obtained his MS and PhD and then worked as Research Assistant, Research Associate and Postdoctoral Fellow. He then did 1 year’s research on aeroacoustics as a research fellow at Hong Kong University of Science and Technology before taking his current position at SJTU. Dr. Yang’s current research interests are aircraft engine noise and new materials/structures for noise control.