Abstract: When the refrigerator compressor run at 3900 rpm, the radiation noise ranged from 1500~3000Hz is loud. The noise easily cause the user to get upset. To reduce the radiation noise, the sound absorbtion cotton is pasted on the cover plate of the compressor cabin, but the sound absorbtion effect is limited, only 0.7 dB(A). To solve this problem, a composite sound absorption structure with micro perforated plate and sound absorption cavity is proposed. To design the sound absorption cavity, the numerical simulation is adopted to calculate the sound absorption coefficient of sound absorption cavity with three sizes, and the size is determined to be 20 mm. After experimental verification, the compressor radiation noise is reduced by 1.74 dB(A) at 3900 rpm, which indicates the composite sound absorption structure is effective to reduce noise.

Key words: Compressor, Sound absorbtion cotton, Micro perforated plate, Sound absorption cavity, Numerical simulation