EXPERIMENTAL STUDY ON FLOW CHARACTERISTICS AROUND TWIN WIND BLADES (RESEARCH NOTE)

In the current study, twin wind blades are designed, fabricated and the effect of various gap ratio (g*) at various angle of attacks (α) on a next to each other twin wind blades are examined in an open-channel wind tunnel. Aerodynamic forces and moments are determined by using three-constraint force balancer. For gap ratio of zero, the aerodynamic attributes are like those of a solitary wind blade edge. As g* increases, these two wind blades actuate the vertical wake to stage vortex shedding modes. With further increment in g*, the wake stream pattern was like those behind a solitary wind blade. For a solitary wind blade, the maximum lift is found to be at α = 30. The pitching moment increases with α. The impact of upper aerofoil blade on the lower one diminished as g* increases.