Design Algorithm of Ventilation Silencer to Reduce Sound Pollution in Air Conditioning Systems

Subject Areas : Journal of New Applied and Computational Findings in Mechanical Systems

Ali Faezian ¹ , Hashem Ahmadi Tighchi ² , Mohammad Mehdi Parsafar ³

1 - Department of Food Machinery Design, Research Institute of Food Science & Technology (RIFST), Mashhad, Iran
2 -
3 - Department of Research and Development, Sanat Prozheh Toos Company, Mashhad, Iran

Received: 2024-11-28 Accepted : 2024-12-31 Published : 2024-12-31

Keywords: Silencer, Air conditioning, Acoustic elements, Sound reduction, Transmission losses,

Abstract :

The sound level and frequency spectrum in air conditioning equipment are key factors in ensuring user comfort. The main sources of sound production in these systems are mainly blower and suction fans, which usually spread through air ducts. Noise pollution control solutions are divided into source control and propagation control, which can be implemented depending on existing conditions, implementation constraints, and costs. Also, during the construction stages of buildings and installation of air conditioning systems, considerations must be taken into account that help reduce the amount of sound emission and transmission. The use of equipment such as silencers, acoustic closures, acoustic rooms, and expansion joints absorbers requires careful design to achieve proper performance. In this article, after reviewing sound reduction solutions, the design of ventilation silencers is discussed. In this type of silencer, the length and number of sound-absorbing baffles, the distance between the plates, and their thickness must be calculated in a way that achieves the best acoustic and hydrodynamic performance. The computational algorithm presented in this study can determine the optimal design of the ventilation silencer that enables maximum sound reduction at the desired frequencies, along with the lowest airflow pressure drop.

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