Recovery of energy from leading-and trailing-edge vortices in tandem-airfoil configurations (original) (raw)
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The wake of a NACA 0012 airfoil oscillating sinusoidal about its aerodynamic center in a general co-flow generates a well-known characteristic vortex street. The introduction of vorticity into the flow in a controlled way could be used as a means to either enhance or dampen any large-scale motion present. The oscillating aerofoil can then be seen as the actuation component of an active control system. To investigate the potential of using a flapping wing as an actuation device the flow field that it generates first needs to be characterized. This can then be used to affect a fluctuating flow field, which in this case is the vortex field generated by an identical oscillating airfoil downstream from the first. Flow visualization coupled with particle image velocimetry is used to investigate and characterize the flow field from both a single oscillating airfoil and the interacting flow field between two tandem airfoils. The relative phase between the two wings is adjusted to investigat...
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