Abstract: Aiming at the problem of wind noise of a refrigerator product, the flow characteristics of its air duct fluid were numerical simulated, and various results are contrastive analyzed. It is concluded that the wind noise is mainly generated by the rotating fan blades and the high-speed air passing through the grid. An optimization scheme is proposed to increase the relative axial position of the fan blade and the grid, and noise reduction is realized by reducing the velocity of air flow through the grid. Then, the fan blade is placed 3.5 mm away from the grid to increase its relative axial position, and the optimized air duct structure is acoustically simulated. It is found that after optimization, the airflow velocity through the grid is reduced, the vortex area formed behind the grid is reduced, and the areas with sound pressure level greater than 20 dB are also significantly smaller. Finally, the noise is reduced by 4.73 dB after optimization according to the calculation of sound pressure level data of each measurement point, which verifies the effectiveness of the proposed optimization proposal.

Key words: Refrigerator, Axial flow fan, Grid, Noise, Numerical simulation