Noise testing of multi-disc fan

The impeller of a multi-disc fan was made of rotating smooth discs spaced close together. The concept of such a machine came from Nikola Tesla in 1909. The fluid, based on the principle of friction against the rotating surfaces of the discs, flows outwards from the disc pack into an outlet. According to the literature, such a design is characterized by low noise emissions. Based on calculations, a prototype of a multi-disc fan was designed and then manufactured. Tests were carried out for the sound power level emitted from the fan's outlet. The examination was performed in a reverberation chamber according to the ISO 3741:2010 standard. The noise source was visualized using an acoustic camera. The aerodynamic characteristics were also determined experimentally according to the ISO 5801:2017 standard. The aim of this study is provide insight into the acoustic and aerodynamic characteristics of a multi-disc fan.