Speaker
Description
The study demonstrated that the acoustic performance of ceiling swirl diffusers with adjustable blades is strongly influenced by both blade geometry and flow configuration. The results showed that some types of commercial profiles significantly increase noise levels, especially under unfavourable conditions of flow. The best performance was achieved by the profile with aerodynamic shape, which produced the lowest sound power levels and even reduced noise below the baseline diffuser. Profile with serrated edges showed good acoustic properties, especially in swirling flow, where it minimised additional noise. The findings highlight the importance of flow direction. Overall, optimised blade geometry and proper flow configuration are essential for designing low-noise swirl diffusers.