Microperforated Panels to Attenuate Air Flow Noise Inside a Duct

Since Microperforated panels (MPPs) can serve as effective, fiber-free replacements for traditional porous materials, they are a good alternative acoustic surface treatment for several industrial applications such as automotive, aerospace, architectural applications, etc. In addition to the acoustic performance of MPPs, the major differentiator of MPPs from conventional acoustic materials is that they can be used as structural elements if they are properly designed. For instance, MPPs can be used as a structural replacement for heating, ventilating and air conditioning (HVAC) ducts. In this study, it will be shown how an MPP can be an effective acoustic control element in ducts by attenuating major noise sources such as fan noise and duct acoustic cavity modes while still maintaining the duct