Abstract

RASTELLI, Victoria H; RASTELLI, Victor  and  MONTBRUN, Nila. Chillers noise control through double walls in a five star Inn in Caracas. Rev. Téc. Ing. Univ. Zulia [online]. 2017, vol.40, n.2, pp.113-122. ISSN 0254-0770.

Noise control main goal is to improve conditions for workers, neighbors or users of establishments such as hotels. Usually air condition Chillers are placed on the roofs of these buildings, on the other hand, exclusive suites are frequently placed on the highest floors of the hotel buildings and could be affected by noise. Noise levels inside rooms, could be structural or aerial driven. In this case study, some guests of the expensive suites, complained for the noise generated by the compressors above. Initially it was suspected that this was a structure vibration problem, and calculated springs mounts were chosen to substitute the original mountings, achieving a partial attenuation. Vibration measurements were made on the chillers, over and under spring mountings, rooftop and room ceiling. The vibration signal analysis showed that mechanical vibrations were not a major cause of concern. So it was concluded that airborne noise was the cause. It was found that the critical resonance frequency of the ceiling plate transmission loss curve was very close to the rotation frequency of the compressors. The solution was calculated employing a double roof false ceiling, where the attenuation was maximized on the critical frequency.

Keywords : noise; control; vibrations.