Fig. 1
From: An aeroelastic wind energy harvester with continuous orbiting motion and no friction components
Orbiting blade energy harvester: axisymmetric airfoil mounted to an elastic beam. Lift and drag forces are shown acting on the circular blade. When the projection of the aerodynamic force on the blade direction of motion is positive, the blade orbiting accelerates. Observe that the apparent wind speed is formed by the free stream flow velocity and the blade’s own orbital motion. Inset: the circular ark airfoils are formed by two spheres of radii \(R_1\) and \(R_2\) and assigned nominal angles \(\alpha\), which is associated with the angle of the leading edge to the disk plane. Angles of the windward and leeward surfaces to the blade plane are \(\theta _2\) and \(\theta _1\) respectively.
