In this study, experiments and numerical simulations were carried out to evaluate the effects of radially distorted incident flow on the performance of axial-flow fans, which were equipped with three kinds of forward-skewed blades. Loss coefficient and velocity components at exit section as well as overall performance are discussed, both at the design point and the lower mass flow rate point. Furthermore, rotating stall was also observed by use of three dynamic pressure sensors. All results reveal that there are beneficial effects of forward-skewed blades on the fan performance, but the fan performance and its unsteady aerodynamic characteristics are quite affected by the radially distorted incident flow.

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