Abstract: With the increasing volume of high-end refrigerator and the development of cryogenic technology, the size and working speed of centrifugal fan are increasing due to the demand of refrigeration performance, so the noise problem of large size fan become more and more prominent. The noise mechanism of the large size centrifugal fan and duct are investigated, through the simulation calculation and experimental testing, the critical factors in affecting noise are identified. By structure design of large size centrifugal fan duct, a balance between the performance and noise is achieved, which makes the performance meet the user requirements.

Key words: Refrigerator noise, Centrifugal fan duct, Noise reduction design