Abstract: The sales of fresh air conditioners are increased year by year with the the development of urbanization and the demand of comfort health and aesthetics. It has attracted more and more attention from consumers of the fresh air volume and the fresh air noise, and it has become increasingly prominent of the troubles caused by fresh air aerodynamic analysic. Therefore, in order to improve the aerodynamic performance and noise value of multi-blade centrifugal fans, the research conducted a full-parameter optimization design of a single arc blade based on a combination of CFD numerical simulation and experiments. It is used by the response surface design method to perform parameterized design on the blade's inlet installation angle βb₁, outlet installation angle βb₂, blade inner diameter D₂, and blade number Z. The relationship between blade parameters, air volume and power were obtained after multiple sets of scheme calculations. The results show that by adjusting the impeller parameters, the flow field distribution in the blade flow channel is improved, the work capacity of the blade is effectively improved and the fan noise performance is reduced. Compared with the prototype, the measured noise at the same air volume is reduced by 0.8 dB(A) and the power is reduced by 11.8%.

Key words: Fresh air volume, Fresh air noise, Multi-blade centrifugal fan, Single arc blade, Parametric design, Aerodynamic performance