Reduction of low-frequency noise from a built-in refrigerator using a perforated plate system

This paper investigates the reduction of low-frequency noise emitted from the machine room of a built-in refrigerator using perforated plate system composed of perforated panels and sound-absorbing materials. The study employs theoretical methods, Finite Element Analysis (FEA), and impedance tube experiments to compare and analyze absorption characteristics across different shapes of perforated panels, aiming to propose an optimal configuration. Simulation of radiated sound power levels demonstrates a decrease in the low-frequency band of the Sound Power Level (PWL) upon implementing perforated plate system. Experimental noise tests conducted in a semi-anechoic chamber validate the effectiveness of the perforated plate system.