INFLUENCE OF COMBINED FLOW CONTROL ON HYDRODYNAMIC CHARACTERISTICS OF TIDAL TURBINE HYDROFOIL
In order to improve the overall hydrodynamic characteristics of tidal turbine blades,this paper introduces the combined flow control method based on Gurney flap(GF)and Vortex generators(VGs)into the field of turbine blade design,and studies the mechanism of the combined flow control approach on the hydrodynamic characteristics of turbine blades.With NACA 4418 hydrofoil as the research object,the three-dimensional models of tidal turbine hydrofoils installed with GF,VGs and their combination are established respectively,and the influences of GF,VGs and their combination on the hydrodynamic performance of turbine blades are studied by numerical simulation method.The comparative research results indicate that the lift coefficient of the hydrofoil section can be effectively improved by installing GF,but the stall angle of the hydrofoil is reduced;the installation of VGs can suppress the flow separation on the suction surface of the hydrofoil section and increase the stall angle,but the improvement in the performance of the hydrofoil is not obvious as the angle of attack becomes small;the flow control combination of GF and VGs can combine their advantages,and it not only improves the lift coefficient of the hydrofoil section,but also suppresses the flow separation and increases the stall angle of the hydrofoil,thus achieving the best flow control effects.
tidal current energyblade hydrofoilnumerical simulationGurney flapvortex generatorscombined flow control