Abstract
The paper presents CFD case studies on vortex shedding from an asymmetric RAF-6E airfoil profile being a representative of low-speed axial fan rotor blades, for angles of attack of α = 0.0°...2.7°, and chord-based Reynolds numbers Rec = (0.6...1.0) · 105. The shed vortices were identified on the basis of Lagrangian-averaged vorticity deviation. An organized dataset has been established for a comprehensive overview of the profile vortex shedding (PVS) phenomenon, enabling order-of-magnitude estimation of data and trends related to the size, rotation, circulation, and travelling velocity of the vortices. Literature-based rotationally symmetric aerodynamic models, as well as a simplified description of source term of vortex sound were applied to the shed vortices. On this basis, an enhanced modelling of PVS has been carried out for a straightforward and yet adequate consideration of the concerted aerodynamic and aeroacoustic aspects of PVS. Such modelling can give a contribution to preliminary fan design by taking the effects of PVS into account on blade vibration and fan noise.
