基于仿生学的MC9风扇改进与信噪比分析OA北大核心CSTPCD

To suppress the noise of the cooling fan for a domestic hydraulic excavator,a 3D model of the fan was printed based on the principle of similarity,and its aerodynamic behavior and noise were tested in a wind tunnel complied with State Standard GB/T1236-2017 and SB002-1987.Then,based on the principle of Bionics,the noise reduction structure involving slot width,stripe spacing and stripe width was proposed,and the corresponding 9 orthogonal test schemes were determined.Then,after the screening of energy saving,the aerodynamics performance,noise,and acoustic image of the schemes were compared with the original scheme to select the feasible schemes.Finally,the contribution rates of the structural parameters were harvested from Signal-to-noise ratio(SNR)analyses.It is found that improved scheme 9 can lower the shaft power by 2%,but increase the flow rate and static pressure peaks approximately by 5.8%.Meanwhile,improved scheme 3 has relatively better noise reduction effect and the noises at the monitoring points are reduced by 2.4,2.1,3.3 and 2.8 dB respectively.The contribution rates of slot width,stripe spacing,and stripe width are 40.45%,33.61%,and 25.94%,respectively.