The noise study of ceiling swirl diffuser with serrated adjustable blades

In this study, measurements of the aeroacoustic properties of air terminal devices (ATDs) control room ventilation. As a study object the ceiling swirl air diffuser with adjustable blades was chosen. These are mechanical devices designed to control fluid flow and create a swirl to supply air into rooms. They are also the source of the noise in rooms. In this work, the new construction of blades was proposed based on the owl's wings. The blades were printed on a 3D printer from ABS and polished. The two positions of attached blades to the front panel of the diffuser were studied - when the serrated and unseratted edge was leading edge. The front panel of the diffuser with blades was installed on the plenum box with a side entry without the damper. The measurements were made in the reverberation room according to ISO 5135 to find the blade's position with lower noise parameters.