Experiment-Based Preliminary Design Guidelines for Consideration of Profile Vortex Shedding From Low-Speed Axial Fan Blades

Abstract This paper presents hot-wire measurements in a wind tunnel, close downstream of basic models blade sections being representative for low-speed, low-Reynolds number axial fans, order to explore the signatures vortex shedding (VS) from profiles. Using Rankine-type approach, an analytical model was developed on velocity fluctuation represented by streets, as aid evaluating experimental data. The profile VS were distinguished blunt trailing-edge based Strouhal numbers obtained case-specific manner. Utilizing results, semi-empirical available literature predicting frequency extended low-speed fan applications. On this basis, quantitative guidelines consideration preliminary design fans moderation VS-induced vibration and noise emission.