Abstract
With electrification of vehicles, compactness/lightness and quietness of HVAC is required, to improve electricity consumption and cabin comfortability. In this study, applying sound-absorbing structures using perforated panels target to HVAC to reduce noise without changing its overall size. The challenge in applying sound-absorbing structures to HVAC was considered to be the change in sound absorption characteristics depending on the sound incident angle. To meet this issue, we introduced partitions in the air cavity behind the perforated panel. The design method of the partitions was studied experimentally, and the evaluation in an actual HVAC unit confirmed that a sound-absorbing structure using perforated panels could reduce noise at the targeted frequency.
