一种多翼离心风机流场模拟与性能分析

Flow field simulation and performance analysis of a multi-blade centrifugal fan

综合多叶片离心风机噪音低以及长短叶离心风机气流稳定的优点,设计了一种具有大小叶片交错组合结构的多翼离心风机。采用计算流体力学方法,分别模拟了前向式和后向式2种不同叶轮形式的风机流场。通过对比发现,在相同转速和流量下,后向式风机进出口压差比前向式叶轮风机小11.8%,但功率消耗降低了24.5%,综合效率较前向式高;后向式风机消弱了涡舌出口处二次流现象,使能量损失降低,同时还减小了涡舌出口处气流的偏斜;但气流在后向式风机内的运动轨迹线较长,改进叶轮的弯曲度是这种后向式风机优化的方向。

Combining the advantages of low noise on multi-blade centrifugal fan and stationary gas flow on splitter blade centrifugal fan,a kind of multi-blade centrifugal fan with splitter blades was designed.By computational fluid dynamics method,the flow fields stirred with forward curved blade and backward curved blade were both simulated.By comparison,it shows that with the same revolving velocity and fluid flux,the pressure drop between inlet and outlet in backward curved blade is 11.8% lower than that in forward curved blade,but the power consumption of the backward curved blade decreases by 24.5%,and the overall efficiency of the backward curve blade fan is higher than that of the forward;the backward weakens the secondary flow phenomena in the vortex tongue exit,thus decreasing energy consumption,and it also restrains the flow deflection.However,the gas trajectory in the backward curved blade fan is longer,and improving impeller bending degree is the optimization direction for the backward curved blade fan.