Abstract: According to the three structural parameters of the baffle inside the centrifugal fan, including the horizontal Angle θ, the length L and the through-hole diameter D, the response surface method was used to design different parameter combination schemes, and two groups of optimization schemes were obtained. RNG k-ε turbulence model is used to simulate the internal flow of centrifugal fan. The test method is used to verify the uniformity and noise performance of centrifugal fan. The results show that the influence of Angle θ on the uniformity of air discharge is the most significant. In optimization scheme 1, the air outlet uniformity and aerodynamic noise performance are the best. At this time, θ=33.06°, L=43.33 mm, D=4.67 mm, and the standard deviation σ of wind speed value at each measuring point of outlet decreases from 1.42 to 0.65, with a decrease of 54%. The measured noise value is reduced from 43.6 dB(A) to 40.2 dB(A), with a decrease of 7.8%. Therefore, optimizing the structural parameters of the baffle can effectively improve the internal flow state of the centrifugal fan, improve the uniformity of the outlet air and aerodynamic noise performance of the centrifugal fan.

Key words: Centrifugal fan, Deflector baffle, Uniformity of air flow, Noise performance, Response surface, Optimization design